[EtgarDizz]

I just turned on debug logging and on looking in the log, the only relevant lines are these:

Code:

20:01:04 T:140735141077760   DEBUG: Addon skin.quartz.mod requires xbmc.gui version 5.0.1 which is not available

Looking at the code for xbmc.gui addon:
https://github.com/xbmc/xbmc/blob/master.../addon.xml

I can see there's backwards compatibility only until 5.3.0
Since I'm requiring 5.0.1, that causes the failed install.

I will have to look into this myself in greater depth to check for other errors.

In the meantime, you're welcome to experiment a little and help with testing...
Here's a link to a test addon, after changing the xbmc.gui requirement to 5.3.0. Let me know how it works!