Up till now the Academic Free License 3.0 was used for all Squareness skins. Since AFL is considered incompatible with GPL I'm changing the license to a BSD-style license. Squareness Look And Feel is the first released under this new license. Other skins will follow as they are updated. For the other skins the license change isn't critical since they aren't used as libraries. So it may take some time till all skins are updated.

Colorizer is licensed under the Open Source License. It is a bit more restrictive than the AFL. It is comparable to GPL and has similar effects on derivative works, but it isn't intended to be used as a library, so it shouldn't matter. Here is the full text: http://opensource.org/licenses/osl-3.0.php