I am on Fedora Core 6 and every time i try and restrict movement to the z axis, it crashes and goes back to the login screen. Has anyone else had this problem, or know how to fix it?
Run Blender from the shell or terminal and see if it gives any error messages.
I don’t think you’ll be able to read it though since you’re logged out as soon as it occurs.
no, i cant read it because i am being logged out 
thanks anyway