I found my problem, I use Onebag and Onebank but I'm now getting an error that is affecting other mods:
Interface\AddOns\OneView\libs\OneStorage-2.0\OneStorage-2.0.lua:42:attempt to call method 'SetupEventsAndInitialSave' (a nil value)
If I disable Onebag/Onebank then everything is fine, I'll post this in the Onebag forum. Sorry but I wasn't getting the error message before.
Disable OneView if you are using it...I had it enabled, was receiving the same error which was causing my oSkin to stop working. I disabled OneView (Onebag/Onebank still enabled) and oSkin worked fine... :)