If you try to use two users sharing via a SAMA share or Windows server it appears you can lose data.
We tested using crossover-pro 4.2-2 on a debian system
It was possible to open the file twice by to users in single user mode.
Tried a second way by mounting via a samba mount and still no joy.
Looks like multi user mode is quite broken.
We ended up with a file that asked to be rolled back but would then crash QB on both windows and Linux systems.
IF others confirm this - the application should not be listed bronze at this time.