Popular (and free) 3D modeling tool Blender is now version 2.57, as per the official release in April. This tool is very often used by consumer designers and makers to produce solid models for 3D printing. Blender sometimes gets a bad rap due to its rather difficult learning curve. But if you can get through that, you'll find Blender does almost everything.
What's new in version 2.57? From their release announcement, 2.57 includes a very large number (500+) bug fixes. We suspect the massive user interface and other changes introduced in version 2.5 came with a few problems that may now be fixed. It may be a good time to get back to Blender if you've been elsewhere. Version 2.57 also includes all of the features originally planned for 2.5 but were postponed.