I had the same thing happen is my last PB too, I think it has to do with walking between the diamonds but I'm not 100% sure.

What items out of the new ones are considered starts if any?

I know I am late to the discussion but I wanted to give my 2-cents. Because it would be so hard to enforce the "No read only" file rule I don't think it should be banned, and since overflow is a game mechanic it shouldn't be banned (plus sometimes it happens on accident) but rather limit the number of times you can overflow during a run. I would think it would be fair to aloud it to be done twice that way you can still use the game mechanic, you can use the read only "strat" (mostly so you dont have to replace your files every other day) and still be able to legally use the donation machine.

The reason why I picked twice rather then three times is since you have 3 files you would be able to overflow 2 of them then bomb out the 3rd where as if you overflow (overflowed?) 3 then you shouldn't be able to bomb out the donation machine which can happen by accident when trying to kill the shop keeper for the devil deal chance.

I understand that the honor system has worked for a long time with this game but me being cynical as I am, think it would be best in order to make as little things be based on honor as possible for the fairness of everyone.