If you use flag /? DO it will give you the full list of directory commands available. Otherwise C in group properties is for change, remove the ability to change eliminates their ability to rename directories. E allows them to erase, M is modify.Are you trying to stop gaming on the network? If so company policy should already be there for misuse of company property. Find names and prosecute by using ndir to show who is cerating and using the files there. If it is acceptable to game on company time or lunch/after hours then where's the issue? Or did I missread this whole thing? It's just the directory name which keeps getting changed. OK, the problem with netware is your rights carry through to subdirectories and they are treated the same as files so if you give them the rights to modify then they have the rights to rename inhibit.
Good luck!