Hi Tom. First of all, thank you for easystroke, it's a 'must have' software in a tablet.

I don't use ubuntu anymore, I've moved to Arch. I've found that easystroke behavior depends on if evdev driver is built with or without mtdev, so I have just tested

- easystroke 0.5.5.1 from Arch repo
- easystroke 0.5.4 compiled from sources, replacing 'lboost_serialization_mt' with  'lboost_serializationt' in Makefile

and

- xf86-input-evdev 2.7.3 from Arch repo (mtdev is a dependence)
- xf86-input-evdev 2.7.3 built from Arch PKGBUILD but removing the mtdev dependence

I have 2 scroll gestures, named 'Gesto 3' and 'Gesto 4'. These are the results of the 4 combinations, I've repeated 3-4 times the gestures in gnome-terminal. By the way, I use LXDE with openbox.

*** easystroke 0.5.4+evdev without mtdev: scroll is PERFECT! (there are other problems with the touchscreen, but not the scroll) ***
root@perl ~ # easystroke -vvvv
Loaded preferences.
Loaded actions.
grabbing: None
Opened Device 9 ('eGalax Inc. USB TouchController': absolute, pressure).
grabbing: Button
Entered window 0x1a00004 -> 0x1a00004
Entered window 0x1c00004 -> 0x1c00004
Press (XI2): 1 (1142,593, 420,763) - () at t = 622548
Giving focus to window 0x1c00004
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1137,256, 297,759) - () at t = 622807
Executing Action Gesto 4
New event handling stack: Idle Scroll 
Press (XI2): 1 (1156,600, 435,013) - () at t = 623625
Release (XI2): 1 (1102,572, 491,265) - () at t = 628466
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1158,601, 206,256) - () at t = 630000
Giving focus to window 0x1c00004
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1149,930, 294,384) - () at t = 630203
Executing Action Gesto 3
New event handling stack: Idle Scroll 
Press (XI2): 1 (1156,600, 187,131) - () at t = 631252
Release (XI2): 1 (1122,582, 477,765) - () at t = 637324
New event handling stack: Idle 
grabbing: Button
Entered window 0x0 -> 0x1a00004
Entered window 0x1a00004 -> 0x1a00004
Press (XI2): 1 (79,374, 735,772) - () at t = 639937
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (80,042, 735,397) - () at t = 640054
New event handling stack: Idle 
grabbing: Button
^CExiting...


*** easystroke 0.5.4+evdev without mtdev: scroll is PERFECT! (there are other problems with the touchscreen, but not the scroll) ***
root@perl ~ # easystroke -vvvv
Loaded preferences.
Loaded actions.
grabbing: None
Opened Device 9 ('eGalax Inc. USB TouchController': absolute, pressure).
grabbing: Button
Entered window 0x1a00004 -> 0x1a00004
Press (XI2): 1 (1161,936, 207,006) - (27872,000, 8832,000, 976,000) at t = 65218
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1153,265, 280,134) - (27664,000, 11952,000) at t = 65382
Executing Action Gesto 3
New event handling stack: Idle Scroll 
Press (XI2): 1 (1151,264, 222,757) - (27616,000, 9504,000, 542,000) at t = 65954
Release (XI2): 1 (1151,931, 533,641) - (27632,000, 22768,000) at t = 74399
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1147,929, 457,889) - (27536,000, 19536,000, 710,000) at t = 75602
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1142,593, 396,387) - (27408,000, 16912,000) at t = 75812
Executing Action Gesto 4
New event handling stack: Idle Scroll 
Press (XI2): 1 (1145,927, 439,888) - (27488,000, 18768,000, 1860,000) at t = 76268
Release (XI2): 1 (1143,927, 561,392) - (27440,000, 23952,000) at t = 78125
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1157,267, 190,131) - (27760,000, 8112,000, 1809,000) at t = 79085
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1138,590, 262,508) - (27312,000, 11200,000) at t = 79241
Executing Action Gesto 3
New event handling stack: Idle Scroll 
Press (XI2): 1 (1150,597, 187,881) - (27600,000, 8016,000, 1090,000) at t = 79728
Release (XI2): 1 (1125,250, 486,015) - (26992,000, 20736,000) at t = 82107
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1143,927, 444,389) - (27440,000, 18960,000, 1990,000) at t = 82807
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1141,258, 373,136) - (27376,000, 15920,000) at t = 82962
Executing Action Gesto 4
New event handling stack: Idle Scroll 
Press (XI2): 1 (1147,262, 426,013) - (27520,000, 18176,000, 2047,000) at t = 83406
Release (XI2): 1 (1133,254, 532,141) - (27184,000, 22704,000) at t = 85149
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1148,596, 212,256) - (27552,000, 9056,000, 2047,000) at t = 86120
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1132,587, 291,384) - (27168,000, 12432,000) at t = 86319
Executing Action Gesto 3
New event handling stack: Idle Scroll 
Press (XI2): 1 (1147,929, 201,006) - (27536,000, 8576,000, 1741,000) at t = 86669
Release (XI2): 1 (1123,916, 498,015) - (26960,000, 21248,000) at t = 90954
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1139,924, 426,013) - (27344,000, 18176,000, 1810,000) at t = 91649
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1137,256, 386,637) - (27280,000, 16496,000) at t = 91759
Executing Action Gesto 4
New event handling stack: Idle Scroll 
Press (XI2): 1 (1138,590, 433,513) - (27312,000, 18496,000, 1497,000) at t = 92183
Release (XI2): 1 (1122,582, 495,765) - (26928,000, 21152,000) at t = 94090
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1166,605, 198,756) - (27984,000, 8480,000, 1940,000) at t = 95029
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1156,600, 255,383) - (27744,000, 10896,000) at t = 95216
Executing Action Gesto 3
New event handling stack: Idle Scroll 
Press (XI2): 1 (1166,605, 187,131) - (27984,000, 7984,000, 1279,000) at t = 95624
Release (XI2): 1 (1137,256, 440,263) - (27280,000, 18784,000) at t = 98504
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (77,373, 729,772) - (1856,000, 31136,000, 410,000) at t = 104308
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (77,373, 727,522) - (1856,000, 31040,000) at t = 104447
New event handling stack: Idle 
grabbing: Button
^CExiting...


*** easystroke 0.5.5.1+evdev without mtdev: scroll is BROKEN, UNUSABLE. It moves very slow and discontinous, windows seems like it was frozen. ***
root@perl ~ # easystroke -vvvv
Loaded preferences.
Loaded actions.
Opened Device 9 ('eGalax Inc. USB TouchController': absolute, pressure).
grabbing: Button
Entered window 0x80022c -> 0x1a00004
Entered window 0x8001d2 -> 0x2200004
Press (XI2): 1 (1171,941, 210,006) - () at t = 58948
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1161,269, 295,884) - () at t = 59163
Executing Action Gesto 3
New event handling stack: Idle Scroll 
grabbing: Raw
Press (XI2): 1 (1154,599, 240,757) - () at t = 60429
Release (XI2): 1 (1143,927, 154,505) - () at t = 61826
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1165,271, 436,888) - () at t = 63666
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1151,264, 331,510) - () at t = 64003
New event handling stack: Idle 
grabbing: Button
XError: BadWindow (invalid Window parameter): X_ChangeWindowAttributes
XError: BadWindow (invalid Window parameter): X_GetProperty
Press (XI2): 1 (1189,283, 195,756) - () at t = 69644
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1179,278, 271,508) - () at t = 69853
Executing Action Gesto 3
New event handling stack: Idle Scroll 
grabbing: Raw
Press (XI2): 1 (1187,949, 207,381) - () at t = 71822
Release (XI2): 1 (1181,946, 303,384) - () at t = 72339
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (81,376, 725,272) - () at t = 75091
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (81,376, 724,522) - () at t = 75207
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (413,548, 665,270) - () at t = 77075
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (415,549, 666,395) - () at t = 77196
New event handling stack: Idle 
grabbing: Button
Entered window 0x80022c -> 0x1a00004
ccPress (XI2): 1 (98,718, 728,272) - () at t = 85021
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (98,718, 728,272) - () at t = 85154
New event handling stack: Idle 
grabbing: Button
^CExiting...


*** easystroke 0.5.5.1+evdev with mtdev: scroll is BROKEN. It doesn't move, scroll does NOTHING AT ALL ***
root@perl ~ # easystroke -vvvv
Loaded preferences.
Loaded actions.
grabbing: None
Opened Device 9 ('eGalax Inc. USB TouchController': absolute, pressure).
grabbing: Button
Entered window 0x800586 -> 0x1a00004
Press (XI2): 1 (1165,271, 192,756) - (27952,000, 8224,000, 1191,000) at t = 118238
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1159,268, 259,133) - (27808,000, 11056,000) at t = 118432
Executing Action Gesto 3
New event handling stack: Idle Scroll 
grabbing: Raw
XError: BadWindow (invalid Window parameter): X_ChangeWindowAttributes
XError: BadWindow (invalid Window parameter): X_GetProperty
Press (XI2): 1 (1157,934, 212,256) - (27776,000, 9056,000, 337,000) at t = 119170
Release (XI2): 1 (1131,253, 389,637) - (27136,000, 16624,000) at t = 123854
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1143,927, 170,630) - (27440,000, 7280,000, 1486,000) at t = 125173
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1127,918, 252,758) - (27056,000, 10784,000) at t = 125394
Executing Action Gesto 3
New event handling stack: Idle Scroll 
grabbing: Raw
Press (XI2): 1 (1131,253, 184,881) - (27136,000, 7888,000, 1021,000) at t = 125981
Release (XI2): 1 (1145,927, 135,004) - (27488,000, 5760,000) at t = 127322
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1148,596, 442,138) - (27552,000, 18864,000, 2047,000) at t = 127964
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1139,924, 325,885) - (27344,000, 13904,000) at t = 128125
Executing Action Gesto 4
New event handling stack: Idle Scroll 
grabbing: Raw
Press (XI2): 1 (1157,934, 459,389) - (27776,000, 19600,000, 2047,000) at t = 128760
Release (XI2): 1 (1141,925, 215,257) - (27392,000, 9184,000) at t = 131338
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (1162,603, 156,380) - (27888,000, 6672,000, 2047,000) at t = 131984
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (1144,594, 249,758) - (27456,000, 10656,000) at t = 132161
Executing Action Gesto 3
New event handling stack: Idle Scroll 
grabbing: Raw
Press (XI2): 1 (1154,599, 174,005) - (27696,000, 7424,000, 2047,000) at t = 132595
Release (XI2): 1 (1134,588, 232,132) - (27216,000, 9904,000) at t = 135855
New event handling stack: Idle 
grabbing: Button
Press (XI2): 1 (74,038, 732,772) - (1776,000, 31264,000, 727,000) at t = 137190
New event handling stack: Idle Stroke 
grabbing: None
Release (XI2): 1 (74,705, 732,022) - (1792,000, 31232,000) at t = 137306
New event handling stack: Idle 
grabbing: Button
^CExiting...

The behaviour I had in Ubuntu 12.04 (also LXDE+openbox) when I post this bug was exactly the same than xf86-input-evdev with mtdev: 0.5.4 is PERFECT, 0.5.5.1 does NOTHING. I think that ubuntu package is called xserver-xorg-input-evdev 2.7.0, I suppose it's built with mtdev support.

Wish this information helps. Please ask for any test I can do in my tablet.