Probably the easiest way is to make gibrack/maps a symbolic link to ../baseq2/maps, assuming your server is powered by some kind of Unix or GNU/Linux, although NTFS supports symlinks (directory junctions) as well. However, lest you forget that every time you run a dedicated server on Windoze, God kills a kitten.
I believe I've understood you correctly. Depending on your HTTP server it should be possible via symlink or some special configuration, like URL mapping in case of Apache for example. This, naturally, implies that you have control over your server (have rights to configure it).
sP1Sp0pD is correct, this is the proper way to do it on a server where you have file system level access. (You may have to link each map instead of the whole dir, but I don't know about that specific mod).
The problem most likely is that macanah does not have FS level access.
macanah: Do you use some web interface to control the server? Or do you have shell access (do you know what SSH is)?