I am having a problem with the item_dropper instance. It always dispenses a blue cube without blue paint powers (even tough I don't want either of those). How do I get it to dispense a regular cube?

What instance are you using? That could help us identify the problem.

Also, take a read of this page to see if you have done it correctly.

A normal box dropper instance is located 'instances/gameplay/cube_dropper_normal.vmf'.

I used item_dropper, I have nto tried cube dropper