I'm having a problem with the srew modifier in Blender. Instead of a nice circle, it produces an oval!
I have the problem with both 2.76 and 2.76b, and I run Ubuntu 15.10. I've probably done something wrong, but what?
Update: here's the blend file: (as the problem is solved, I removed the link).
The problem is regarding the red object (it's selected in the image below). (I had to remove one screenshot to add the link...)