This mostly just reduces the nesting to something more sane.

Comparing gl_shaders against NULL after potentially dereferencing it a few
lines earlier probably confuses Coverity. Checking num_gl_shaders instead
should avoid this.

This was partially handled by ungetting the end group token (i.e. '}')
so that it was read again at the proper place.  Unfortunately there is a
read hook that maintains a stackTop variable, which is decremented when
receiving this end group token.  Therefore stackTop would get
decremented twice, and the rich text file would end prematurely.

This is fixed by incrementing the stackTop variable to compensate for it
being decremented twice.

The DirectX SDK reports that cooperative level flags
DDSCL_SETDEVICEWINDOW and DDSCL_SETFOCUSWINDOW are only
available on Windows 98 and higher.