Score sprite spawning was broken on both LoROM and SA-1. On LoROM, it was a simple fix because the routine you call expects a sprite in X, so all that has to be done is move Y into X before calling it, then restore both of them.
SA-1 is a little weird. The remap moves some sprite tables ($9E, $D8, and $E4) out of the direct page. To avoid having to move or hijack every single routine which references them, it places pointers to the correct index in the table at $B4, $CC, and $EE. The score sprite routine uses both $D8 and $E4, so I had to calculate and store the correct pointers in $CC and $EE. As I said, I'm not sure if there's a better way to do it, but it's at least better than copying over the whole routine.
I knew about score sprites not spawning correctly issue, but nobody answered me how to fix it when I asked.
For $19 and $0DC2 - yeah, I forgot to fix it, but submission was under moderation already, so... I mean I could've submitted the fix, but I didn't wanted to disturb moderator. :shrug:
This is a very good alternative for those who want custom powerups without inserting anything too complicated. Adding new powerups is very easy for those who have basic ASM knowledge.
I should note that I fixed three things during the moderation. The item box contents were being incorrectly set (the values for $19 and $0DC2 don't match up), so I made it use a lookup table. I also fixed score sprites from killing enemies (though I'm not sure if it's the best way for SA-1), an issue which I missed during the previous moderation and so will not count as a rejection reason for this update. Finally, I reconstructed the correct graphics for the boomerang from the GIF, so now the included graphics file will work out of the box.
Fixed most of issues pointed in removal log. Not sure what means "the boomerang is in the wrong place", is it like sprite tile's angle? As for "Item Box Special" patches support thing: I've considered that for next update, after this submission gets accepted.