hIDE uses low-level GHC APIs to do some of its tricks. Unfortunately, GHC APIs change faster than hIDE, so the last version of hIDE is not compatible with GHC 6.6.

As far as I know, in GHC 6.6 moduleFS has been renamed moduleNameFS. You can try to replace "moduleFS" with "moduleNameFS" on line 126 in src/Hide/Plugin/LoaderMidLevel.hs, and try to recompile.

Tell me if you manage to compile it with this fix, hIDE authors could be interested.

Salvatore