Inventorio mod has a lot of incompatibilities with other mods: corpse-like mods don't see what's stored in the extra inventory and utility belt, so does ydm's weapon master (visual appearance of weapons and tools on the character), my guess would be that there are more of them that I just don't use. For now I'm using only a couple of features from Inventorio mod, like having extra button for offhand use (I haven't found any mods for my version of minecraft with that feature) or expanded ender chest (tons of mods bring tons of items). I have Toolbelt and Deeppockets book disabled (deeppockets also had a couple of bugs, like flying when using a particular item from L_ender's cataclysm mod), but I can't disable Utility belt function, to have vanilla offhand and vanilla inventory. Please add Utility belt function disabling option with vanilla offhand slot.