when i use groups for rendering in as particles and select "Whole Group" and then move the size slider under "Render",
the dupligroup objects suddenly rotate by 90 degrees. (They should stand vertically)
To reproduce, change size in test file under "Render" and then maybe uncheck and check "Whole Group".
Blender: rev 52786
OS: Mac OS X 10.7.5
CPU: I7 2600
GPU: Geforce GTX 580
RAM: 16 GB
Closed, ArchivedPublicParticle dupligroup objects rotated unexpectedly
Rotations are undefined in this setup - the cache (or so) is giving problems.
Here's at least a work-around: just enable "particle rotation" (button in panel header) and things go all predictable. It does rotate the group, but you can correct it simply.
I am merging all particle rotation errors in 1 report (5 already).
Sorry, but can't do much more now, the feature is not actively been maintained at the moment.