Okay, with ZDevils help I am now also able to run the Leo outliner.
It was necessary to install the large Python 2.4.1 package. Originally I thought it would be part of pdaXrom anyway, so I didn't care about installing it. But it was not, so many python modules were missing.
Leo starts now without problems, but it takes a minute or so.
In the log window, the font size is too small. This can be adjusted in the settings outline.
Leo is quite slow on the Zaurus. I'd like to avoid overclocking for it, because the outliner will be a centrl app for me which should stay open all the time and available all the time.
So I'll look into optimizatoins, or maybe running an old version.
However, this is just the beginning. I'l have to see if Leo fits my needs (full keyboard operability for example, convenient font size adjustments, features etc.)
If anyone's interested in that, too, let's discuss it here. Maybe we can make Leo a good Zaurus outliner.
There are other options, too, for which I will start different threads as needed.
daniel