Hi Graham,
What were you trying to change it to?
I haven't come across this before, though I had it in the back of my mind that there was a character limit, so just tried setting up a new profile on my spare 'test' Rosetta.
Set up a completely new Profile - including a change of Group ID to EOSM and it worked and saved as expected.
Then tried a longer Group ID BUCKINGHAM - also OK, but BUCKINGHAMPALACE was cut off to BUCKINGHAMPA - i.e. a maximum of 12 characters.
OK so next I tried two words with a space (EOSM GROUP) - This was rejected - but EOSM-GROUP (with a hyphen) was OK.
So it looks like there is a limit of 12 characters, but with no 'spaces'. There may also be a restriction on some other 'non-standard or unusual characters'.
Perhaps Lee can confirm.
If this is correct, I will ask the guys to add it to the next revision of the user manual.
Regards
Peter