Xubuntu installer with usb in UEFI BIOS mode ubiquity GRUB Installer crashed with "grub-efi-amd64-signed" package.

[BenginM]

Today i tried to install Xubuntu 17.04 from USB in legacy BIOS mode , but th installer got stuck at

 " A start job is running for ubuntu live cd
              installer ".

So, on the next attempt i went to boot in UEFI BIOS mode , and then the installer crashed on this # see screenshoot :
https://imgur.com/gallery/n7DU4

I'm reporting this whilst still in the live session of 17.04.

ProblemType: Bug
DistroRelease: Ubuntu 17.04
Package: ubiquity 17.04.9
ProcVersionSignature: Ubuntu 4.10.0-19.21-generic 4.10.8
Uname: Linux 4.10.0-19-generic x86_64
ApportVersion: 2.20.4-0ubuntu4
Architecture: amd64
CasperVersion: 1.380
Date: Tue Aug 8 14:14:59 2017
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/xubuntu.seed boot=casper quiet splash ---
LiveMediaBuild: Xubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
ProcEnviron:
 TERM=unknown
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
 LC_NUMERIC=C.UTF-8
SourcePackage: grub-installer
UpgradeStatus: No upgrade log present (probably fresh install)

[BenginM (sary)]

#see https://bugs.launchpad.net/ubuntu/+source/grub-installer/+bug/1629348

[Phillip Susi (psusi)]

Your disk is currently partitioned to boot in bios mode, but you booted the installer in EFI mode. A warning message prompted you that this could be a problem and recommended performing a bios mode install instead, but you chose not to. You either need to perform the bios mode install, or partition the disk using GPT and set up an EFI system partition to install in EFI mode. This will be done for you if you choose the "use entire disk" guided install option.