Notes for the most recent attempt.

Cut into relatively small chunks – worked very well.
Used rectangle pan 9×12
Don’t use pineapple juice any more – pinapple chunks – yes – pineapple juice no.
Uses 3/8 pound of butter – too much – reduce.
Used 1/2 cup of OJ – reduce to 1/4 cup next time.
Put full layer of marshmellows – that worked – but by the time we got to the place they all had vaporized. Next time, use mini marshmellows and put on at the last minute – perhaps use a microwave at the destination to soften marshmellows.
Next time, put some cornstarch into the OJ. This stayed too soupy.
Remember that the potatoes give off liquid.