Why are you still using v.2.6 ? Here I use wx v2.8, the latest, and Panda 1.5.1. I don’t know since which version startWx was added to ShowBase.
self.SetTransparent :
self is CreateNewFile instance, derived from wx.Frame, so it’s a method of a wx.Frame.
It was developed on Windows. But I have just setup a Hardy box (I’m a 3 days linuxer 
) with the latest NVIDIA driver, and I have Panda’s gutsy .deb v1.5.2, I’ll try it soon on Hardy.
rninne, what’s your graphics card ?
For the previous RTT problem you have, do the render-to-texture samples work ?
RTT setup is tricky, the result varies too much across graphics cards.