[pkscout]

Could you please look into one more issue? It looks like when one listens to multiple songs in a row, AS restarts the slideshow every time a new song starts. Normally it shouldn't be a problem, but with my large collection of images (15,000), every time a new song starts I get ~1 minute of black screen. So overall I only see my photos half of the time Any chance this behaviour can be changed - so that a slideshow is initiated only once (when the first song starts playing), and then stops only when the music stops (either because it reached the end of the song list, or because I pressed the stop button)?

The only use case where the slideshow could keep running is if you're using the override option to show a set of images instead of any artist images.  I'll take a look to see if I can figure out how to keep the slideshow running in that case.  Given that AS 3.1.0 just released this will have to wait until the next release.  The Kodi folks don't like to have addons updated frequently, so I'd say at least a month to 6 weeks for another release (although I can do betas as frequently as I want).
 

Two more points are more minor. First, it'd be great if every time a new song starts the music player stuff would not come on top of the slideshow (with the music fanart, song title, player buttons etc). So basically I want my slideshow to be uninterrupted: the focus is the images, music is just background.

That's a skin decision.  I know the Estuary skin pops that up when I song starts, but I'm not sure about other skins.  The question of how to stop that from happening would be best asked in the skin support area for whatever skin you're using.
 

Second, when I pause music, slideshow keeps running. Ideally, one would want the slides to pause as well - e.g. when you want to spend more time showing a particular photo to your guests.

I'll add that to the list as a potential option that could be enabled for the next release.