Eventually I know why OOo2GD doesn't work on MacOS.
OpenOffice.org for Mac OS is 32 bit application, Apple Java 6.0 for Mac OS 10.5 is 64 bit application. It looks that on Mac OS, exactly the same like on Windows, 32 bit applications cannot use 64 bit Java. Because of this even if OpenOffice.org pointed to Apple Java 6.0 it was truly using Java 5.0 and OOo2GD wasn't able to work.
I compiled some special version [without some features] for Java 5.0 and this version was able to run on Mac OS 10.5 [I have screenshots :-)]
For now this version isn't perfect.
Download doesn't work [but files are downloaded and written on disk, OOo2GD cannot open those files in OpenOffice.org and hangs OO.org ;-)], on some system also upload doesn't work.
Changing of interface language doesn't work, whatever you choose it will be always English ;-)
Some fonts looks strange.
Buttons "Open in Browser" and "Open via Browser" doesn't work [the same as links for my pages ;-)] because of using Java 5.
I still don't know what I will do with version for MacOS, but most probable for now is that I will prepare some special Java 5 version of AddOn [I hope I will be able to keep as many features as possible].
Early access version of OOo2GD 1.7.0 with partial MacOS support
Which language is fastest? ;-)
OOo2GD 1.5.0 - we can download spreadsheets :-)
Mac OS users - call for help :-)
OOo2GD 1.5.1 Birthday Edition ;-)