Quote: "I've got a question regarding the rule about using copyrighted stuff: There's this open source program called MakeHuman that makes 3d character models. Since it's open source, does that mean I can use the meshes it creates in my competition entry? "
This legal information is taken directly from their website.
Quote: "When you export, save, or in any way convert a MakeHuman data file, you may store any deformations that you have applied/created, along with the topology of the base mesh and any positional information that you have not materially changed. You are the Copyright holder of changes that you have made. The MakeHuman Team retains Copyright over the topology and the base mesh, but grants you permission to copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the generated materials over which they hold Copyright, including the topology and positional information constituting the base mesh provided that this does not prevent others from doing the same."
Remember TGC takes no responsibility for what you submit to us. I can't tell you if it's legal or not without putting myself and the company in the firing line.
Read it through, have a look at the full licence here
http://makehuman.wiki.sourceforge.net/Licensing then make up your own mind.