Hi Fernanndo,
First you need an licence for the Stapi modules.
You must ask Ron how can you buy an licence.
to ) My next try will be to install some programs from the STAPI and to try to see how they work in the tribbox. Has anyone got experience doing this ?
Yes I have tested with the tribbox system to use the Stapi modules in this system.
If I have installed the driver for the kernel I can use the graphical output on scart and hdmi on the box.
With an litle modification on

an script from me I can switch to scart and hdmi.
I have installed the Stapi modules in a new path and modify the rc.local script in the tribbox system to load the driver.
to ) Does somebody know about a company/freelancer with experience setting up the tribbox as a DVB settopbox using the STAPI that can provide commercial support ?
About this things ask RonvH. He can more say about this.
regards
Micha