皆様、
I’ve had なさんな and んといて in my ghosts for a little while now but can’t figure out how to tell them apart when reviewing. The prompt for both are ‘please do not’, but are there situations where they’re not interchangeable?
Right now I’m blindly guessing whether it’s 行きなさんな or 行かんといて on two specific sentences…and then of course back to the review pile it goes 
Any advice would be appreciated お願いします
In real life I think they have different nuance but I looked at the example sentences of each and I don’t know how you would tell them apart unless it gives you the verb stem since that is different (for non ichdan verbs anyway).
Just asked my coworker and he said that basically なさんな is more old fashioned and maybe people say it in Kyoto but he never says it (Hanshin area) and he is in his mid-thirties. Equally, like Bunpro suggests, なさんな is more of a prohibition than a request but it isn’t as harsh as straight up verb+な.
As for the Bunpro prompts, I don’t use the Kansai deck so can’t comment. I guess they don’t differentiate well enough.
I would really suggest the book Colloquial Kansai Japanese. It has a lot more information than Bunpro does (sorry for the blasphemy) and I use it as a reference whenever I hear a coworker say something that leaves me feeling clueless. Honestly, one pass through that book and suddenly life in Kansai became 10% more comprehensible.
From my experience I’ve never heard なさんな from my Kansai friends or immersion. I always say んといて or just normal ないで