Scripts not working and "no animation data available for this model"

Hey, guys

I have this project at college, where I need to use scripts for animation, and I chose Unity because it has to have compability with Java, so, JavaScript it is (until now).

I made an humanoid character in MakeHuman, where I added the basic rig, and then exported to Unity. It recognized the rig properly, and I even took some animations from Assets Store, some of them worked.

The problem is: I can't use scripts. I've tried a million tutorials, none of them worked. When I add a script, it seems that Unity can't associate it well to my character, or, when it does, there's no animation. Sometimes, it shows "no animation data available for this model", which I couldn't solve yet. I'm really lost.

Do you have ANY idea of what's happening, or what could I do? I don't know where to start anymore.