Flying a Yak 12 with a round engine in Poland was fun. A bit like a super cub on steroids, but the pilot was never allowed to do a cold start. The aircraft was pushed out of the hangar, pre flighted by one of the mechanics, started, engine checks done. Then one was allowed to remove it from their tender care. On return post flight checks done, fuel as required, cleaned, and pushed back into the hangar. I used to take a couple of cases of Calvados with me from France, and leave a bottle on board after each flight. Strangely enough, there was always an aeroplane available when I wanted to fly, and my normal sized cub got put to bed in the hangar.
Oh, yes, Constant speed prop. Took nearly five minutes to show me what to do. In Polish. Instrument marking in Russian. Never did get any theory told me, but apparently I was considered able to tow gliders with it. Pointy finger, stabbing at the instrument face, lots of this, then this, seemed to work.