Coordinates in group are false (FIXED IN VERSION 2.8.1) (corrigé)
The coordinate system in groups (normally 1000 units= 1 cadrat) have unintentionally changed. Now it seems more like 10000 units = 1 cadrat.
I need to figure out what's going on, but this bug should be short lived.
Unfortunately, it means some groups created meanwhile will become false and need to be rebuilt. (As far as I can guess, I introduced this bug when cleaning up the DrawingSpecification in august 2008) The bug is corrected in my own development version. I consider it serious enough to release a new version very soon.
I advise users to use version 2.8.1 as soon as possible, as it fixes the bug.