Define "doesn't work". What appears, if anything, in the launcher's mods tab? A screenshot of that tab would be nice.
Note that currently, when you add a mod folder to your Diaspora folder, you need to restart the launcher for the mod to appear in the launcher's mods tab. (A "refresh mod list" button is in the plans, but with no ETA at the moment.)
Could you specify the mod you used for reproducing it (with a link to its release thread) and exact steps to reproduce?
Other than that, I might not be able to look at this more closely until this weekend. Perhaps Iss can look at it sooner than that.