How do I reverse the mousewheel direction for zooming?
The default direction for zooming with Ctrl+mousewheel depends from the version of the gecko engine, that’s why it switched between K-Meleon versions 1.5.4 and 1.6. There exists a hidden switch to reverse that direction yourself, if you prefer, but it takes a bit manual work. See explanations in Forum. There’s also a little macro available that creates a simple menu entry for switching.
