Are you talking about Rogue Spear maps or Ghost Recon ones?
If Rogue Spear, then you can check further down in this forum, where there are tips on how to convert mods in general, including maps.
I use VirtualPC, texedit and SoundAppPPC, all of which should be readily available on
www.versiontracker.com - but in some cases you can do away with virtualPC and just use stuffit to expand the .exe files.
But if you're asking about Ghost Recon, I'm afraid I haven't the foggiest yet...
Toby