Tip: If you place a moon, midpoint, or dragon coin through Map16, it will always respawn whenever you reenter that sublevel. It will not respawn if you add it through the Add Objects/Extended Objects window.
I don't know if it has been mentionned before, but I had a problem with the patch. Basically, my game crashed after I got hit while being big Mario after I got the mushroom in the multi coins block. The strange part is, it doesn't happen if I get a fire flower after that for example.