Comment 16 for bug 902843

Saving as 'Optimized SVG' works from within the GUI without failure using
Inkscape 0.48.2 with Python 2.6.7 on Mac OS X 10.5.8 (i386)
MBP late 2008, 2GB RAM, Intel C2D 2.4GHz

Inkscape takes close to two minutes (1'45'') to load the file, grabbing all available system resources (RAM) and outputs a warning to the console:
** (inkscape:43587): WARNING **: GC Warning: Repeated allocation of very large block (appr. size 6254592):
 May lead to memory leak and poor performance.

Saving a copy as 'Optimized SVG' takes about 3-4 minutes on my system until the new file is fully written: the closing of the export options dialog does not indicate that the output extension is finished (you can monitor the Python process in the 'Activity Monitor') - if I remember correctly, Inkscape notifies with a message in the status line when the saving is actually done.

> It gives me an "wait" cursor as it is saving and after some time
> (a minute or maybe more) it returns to my drawing as if it
> has saved the file, but the target folder has no file saved.

Possibly you didn't wait long enough, on either system…?