I think it depends on how the users are creating their files/directories that actually affects the permissions.
I assume they're creating their files through their mapped drive, using Samba.
This post from Damien Curtain (who wrote the original rpm, I believe):
http://e-smith.org/bboard/read.php?f=3&i=5827&t=5699 mentions the /etc/smb.conf file.
After briefly looking at this file, it looks like the smb.conf file specifies the permissions that are to be used when files/directories are created through Samba. I'm thinking that a new section needs to be specified for the "WebFiles" with different permissions in place. Once someone comes up with the working section, it can be put into a template fragment.. and possibly added back into the rpm for everyone to use.
You guys have a little time to play with it? I'll be happy to help with the rpm work when we get to that point.