despite having the map, whenever i try to connect to the server with rp_downtownV1-1p it says the map is not the same version, can you please link me to the correct version?
Just delete or rename the rp_downtown_v1-1p.bsp file to something else and reconnect, gmod will automatically redownload it. (You may find it in "C:\Steam\steamapps\SourceMods\gmod9\maps\")
I am pretty sure you just have to restart Garry's Mod 9 when that message appears. Once you do that try to connect to the server. If that doesn't work you can probably find the map somewhere on Garrysmod.org, but that's if you have Garry's Mod 10.