It seems like they replaced your MyRocks files and such...
Just running FHSetup.exe again should fix it, if not, do what Thrillex said, uninstall, and re-install.
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If their map came with some .fho files that replaced your old ones, don't put those in again, just do the .fhm.
BUT
if it was just a .fhm file that caused this to happen, don't put it back in.