Can I still switch back to black on any of these tilesets, as an alternative background image, like many graphic sets, e.g. by GigaLem, have them? Or is the change to the new backdrops exclusive and permanent?
I'm still kind of on the fence whether I want to use them or not. Having the backgrounds certainly makes levels appear more 3D-like, a bit reminiscent of the way the original Lemmings levels were redesigned by Team 17 for the PlayStation. With just plain black however, it looks more traditional, which I like especially for the more traditionally-spirited Paralems.
As far as I could tell from nin10doadict's videos, a pack automatically fetches the style installed on the user's PC, it is not limited to what the creator chose (I found out about this because he has the backgrounds enabled when playing my pack without me having to implement them, I compiled the .nxp with the original graphic sets). Hence, I conclude the change to the new backgrounds is automatic, not optional on a per-level basis within the editor?