Beginning digging into codebase from an IDE, or at least without installation.

Hi,
this question is more related to a overall usage of Setuptools based software, but as I want to spend some time with Soundconverter (I really like the program and want to try to add some additional features), I dare myself and ask the question here.

Can anybody give me a short advice, how to use Soundconverter in a virtual environment, without installing it and without modifying too much of the existing code.
I thought it would be easy with my Python background, but since years I write console/network stuff, mostly on server side, and never before with a build system like setuptools (we use our own packaging tools, but they have a complete different style).

I just want to open the repo of Soundconverter and run/test/debug the existing files, but just right from the start, this is not successful, caused by the main file relays on pkg_resources.

Any help is welcome, thank you :-)!

Ralph