KDE4 compositing won't switch on : RESOLVED

[Donn]

A follow-up to explain how I 'resolved' the OP.

Nils got me digging in the kwinrc file to fix another issue. I noticed the 
section titled [Compositing] and thought 'erase and rewind'...

1. I opened ~/.kde/share/config/kwinrc
2. I found the section.
3. I erased all the lines for its settings.
4. Saved it.
5. Brought up the window settings box and enabled compositing.
6. Lo! It worked.

FYI: My current working section looks like this:

[Compositing]
AnimationSpeed=3
Backend=OpenGL
DisableChecks=false
Enabled=true
GLDirect=true
GLMode=TFP
GLTextureFilter=0
GLVSync=false
HiddenPreviews=5
XRenderSmoothScale=false

HTH,
\d