After some work, I've come up with this new patchset.
- 0001 is an update of the previous 0001 with most of the issues raised
(hopefully) being addressed. It still uses git from source and wraps
the build and install phase, though.
- 0002 causes the packages to use the main site instead of git.
- 0003 splits renpy into the python package python2-renpy and the
program itself. This makes the build rules a little easier to read,
even if they themselves did not change much.
- 0004 fixes the launcher (mostly). One can now set a project
directory, create projects, launch created projects and open project
directories in the default file explorer. However, setting the editor
(and hence launching one) still does not work.

Regards,

Leo