it should certainly be possible to use all three together in one mod. Missing mesh error means, iIrc, that the game is looking for a model (a mesh) that doesn't exist. This might mean that either it can't find the .brf (make sure it's added to your module.ini-thingie), that it can find the .brf but the mesh isn't in there (in that case simply delete any reference to the mesh it's looking for), or it means you have a typo which might make, for example, the game look for super_armor1 while you saved it as super_armour1.
Mind you, I have no idea why I am back in this part of the forge as I gave up on modding in February. This means that this post might be wrong, and if it's not I might not be able to give more help, if you need any.