Hello,
I'd like to point you to a new section of our official documentation:
http://www.genode.org/documentation/developer-resources/porting
The new "Porting Guide" goes step by step through the process of bringing existing 3rd-party software to Genode. There are dedicated sections for porting libraries, applications, noux packages as well as device drivers.
Of course, each porting effort comes with unique challenges. The porting guide is no panacea to overcome all those problems at once. However, it presents a time-tested methodology and contains a lot of practical tips and tricks.
Thanks to Josef Söntgen and Sebastian Sumpf for authoring the document!
Norman