Try the glut examples with lablglut, they should work.

I guess examples with togl segfault because tk is now supported in  
the native window system and if you compile ocaml it will use the  
native version of tk. However togl uses glx to initalize the opengl  
context so both cannot work together. If you really want to use togl  
you need to compile ocaml so that it uses a X11 version of tk.

Best,

Daniel