I've just upgraded to 2.0.10, on Linux with latest j2re1.6, and am experiencing this problem quite often;
seems something is really b0rked here: on a standalone task, created
with start-end dates - 9 days delta - there's no way to make GP change
end date, it always reverts to original. Changing duration doesn't help either (and BTW won't update end date in task properties panel). Nor...
2009-12-23 12:33:22 UTC in GanttProject
