I think its an issue with the Steam overlay rather than the mod itself. I am using the Steam version of Battlefield 2 and i have had to disable my Steam Overlay as Punkbuster likes to kick me for having an unauthorized device/plugin.
I do understand the annoyance not being able to reply when people send you Steam chat messages etc but so far, i've found it to be the only compromise. You can turn the Steam Overlay off for specific games now instead of turning it off completely.
To do this:
Right Click on Battlefield 2 in your Steam Library.
Click on Properties.
Click the tick box 'Enable Steam Community In-Game'.
Once you have done this, this will turn off the Steam Overlay for Battlefield 2 and Project Reality and should stop your crashes to desktop.