Lemme walk you through the changes I make.
First, stuff like this is a bit of a mess and likely why the import went wrong:
Not sure if this is how you had it in musescore, but there are far too many layers here and it's messing everything up.
Looks like they were messed up further my my copy+pasting, but it looks a lot cleaner like this:
-I also changed the first measure from a 1/8 to a pickup measure, which I'm sure is something that got messed up in the transfer.
-I moved the 2nd voice in m3 to the 2nd layer - voices should be kept to the same layer. As it was, the beaming made it look like beat 2 onward was actually the same voice as beat 1 1st layer.
-There's some places where the bassline is held, but in some of the short repeated notes, like m3's LH, 2 16ths would be better. I took the liberty of changing them. I also added a few staccatos to the LH in the 2nd part.
Some things I'm leaving it up to you to change:
-m15's LH starts with 3 16th notes. I hear it other places, but it did make sense to leave them out for playability reasons. I'm not sure what makes this measure different.
-m11 LH - I'ts not humanly possible to play both layers here. Either pick one, or have the right hand take that higher note.
-The background voice. I'm a bit mixed on how you implemented it. My original idea was that it could play when nothing else was going on in the right hand to give it something to do. Having it everywhere leads to impossible jumps like m1 and a sudden increase in difficulty
-The harmony for the main melody. I wrote out what I heard for the first system; see if you can use that as a starting point to hear the harmony for the rest of it.
-One more thing about the background voice - It changes up in m12
-Measure spacing. Either tweak it so that everything is on one page (more difficult) or so that there are more systems on page 2 (harder, but I
think you can do it with notepad. The reason I'm not doing it now is I think that adding/removing the 2nd layer will change the spacing of the first page somewhat.
Here's the file I fixed. As I said, there is still work to do that can help you be a better arranger by working through it yourself. It's always nice to see new arrangers around here, and this is a pretty solid first sheet, nice job.
