I'll let other users put their views across about this. One point I'd like to make is you can put a description to any type of file. So you could put in your description "only works on XP", so the people who are searching will see that tag & know immediately. To describe a file, select it in the Library window & press Describe button. ... rest is all yours.

Oh & use the Refresh button after that so the information is immediately available to users online who are searching.
This will however mean LW will recount through its shared files. So it may take a while if you have a lot of shared files.