Show movie sets among single movies in smart playlist

Hi, I organize my full movie library in widgets / custom smart playlists, with many films being part of movie sets, but there are two things that are driving me crazy:
1 – When I open, for example, my “science fiction” playlist from Kodi/Videos/Smart playlists, it results in a combined list of individual movies and movie sets, which is exactly what I want, but all movie sets are displaying first, even though I set order to random. Is there a way to have movie sets ramdomly allocated among individual movies?
2 – When I “call” the same smart playlist from the skin’s menu widget of a skin that can handle them (let’s say for example, Arctic Zephir Reloaded), I cannot replicate the same behaviour. All movies show as single movies. No movie sets at all.
Any idea on this?