Fix errors in an import and additional questions.
I'm a hobbyist and have only used Musescore previously to convert PDFs so I'm not an experienced user. I'm now trying to use the program for more things, but I've run into a situation with a .XML export from Reaper 7. When imported into Musescore 4.3, the file gives a message that it is corrupted, but it still can be imported. Most obvious was the sustain pedal info came in misaligned, but I deleted those as they are not necessary for this. However, I noticed that many note lengths have also been altered. The piece is in 3/4 and many first chords in a bar have dotted half notes (3 beats) 
They are not this way in the Reaper notation. The top Bb in the image should only be a half note. However, If I change it in Musescore, it changes all three notes in the chord. Should that happen?
Shouldn't I be able to edit the length of only that note? Is this a function of Musescore, or is the .xml import being corrupted in other ways? Also, when I save I get warning errors that I think are related to this. I think the incorrect note lengths are not adding up for the time signature?
The image is measure 2, and the lowers staff is staff 3 of the first error below.
e.g.
Incomplete measure: Full score, measure 2, staff 3. Found: 7/8. Expected: 3/4.
Incomplete measure: Full score, measure 3, staff 1. Found: 8/8. Expected: 3/4.
Incomplete measure: Full score, measure 3, staff 2. Found: 11/8. Expected: 3/4.
.
.
.
.
Incomplete measure: Full score, measure 4, staff 2. Found: 4/4. Expected:
Incomplete measure: Full score, measure 30, staff 3. Found: 11/8. Expected: 3/4.
Incomplete measure: Full score, measure 31, staff 1. Found: 7/8. Expected: 3/4.
Incomplete measure: Full score, measure 31, staff 2. Found: 13/16. Expected: 3/4.
Comments
Can you post the XML file that is causing the problem? MuseScore may just be saying what it sees and the XML file may not be perfect.
In reply to Can you post the XML file… by underquark
This is the same notation in Reaper. Note that the Bb is not dotted. Must be something in the Reaper conversion.
In reply to This is the same notation in… by artisland08
On first glance, it seems that Reaper got it wrong.
But please listen to underquark, who said: "Can you post the XML file that is causing the problem?"
Pictures only reveal part of the problem, but MusicXML or MSCZ files tell the entire story!
In reply to Can you post the XML file… by underquark
Another odd thing is that it sounds right when played in Reaper, but when rendered to .mp3 or .wav FROM Reaper it does not. Again, I'm a hobbyist so I don't know what I'm doing.
In reply to Another odd thing is that it… by artisland08
"but when rendered to .mp3 or .wav FROM Reaper it does not"
So, it sounds like a Reaper problem, then? Without seeing the XML exported by Reaper, we can only guess.
In reply to "but when rendered to .mp3… by underquark
The .xml file
In reply to The .xml file by artisland08
Reaper has put all notes in the same voice in the MusicXML file. MuseScore simply assumes this to be correct, thus for the piano part all notes go either into staff 2 voice 1 or into staff 3 voice 1. Reaper did correctly encode the Bb3 as a half note without a dot, but because it is in the same voice as the (dotted half) Bb1 and Bb2, it goes into the same chord in MuseScore and in MuseScore all notes in a chord have the same duration, which explains the extra dot.
For reference, the attached image shows the result of importing the file into Finale NotePad, which automatically handles this (note the different colors).
Besides the voice issue, there are a number of other areas where Reaper's MusicXML encoding seems incorrect (e.g. the two dotted quarter notes in measure 3 staff 1 partially overlap, the measure rest in measure 17 staff 1 has a duration of 4/4 instead of 3/4).
In reply to Reaper has put all notes in… by Leon Vinken
Almost every measure of the piano part is incorrect. Just as bad in Sibelius.
In reply to Almost every measure of the… by bobjp
Thanks all for your efforts! I have discovered that the Numa Player Piano VST I was using in Reaper for this is probably causing my problem. Although it plays the MIDI correctly, when rendered to audio it is out of time and off the grid! This has been driving me insane thinking my hearing is off. On a lark, I tried changing the Piano VST and suddenly the MIDI both plays and renders to audio correctly! I suspect this is what resulted in all the corruptions Musescore found in the file.
I made mono renders from Reaper of both Numa Player and Key Zone Classic. I then imported next to the MIDI track. Key Zone sounded correct and aligned perfectly with the midi! Numa did not. Later I will try a Reaper export to Musescore using the Key Zone Piano and see if the MIDI exports correctly.
Again, thanks for all your efforts in helping me.
In reply to Reaper has put all notes in… by Leon Vinken
"in MuseScore all notes in a chord have the same duration, which explains the extra dot."
Hmmm? But we can arpeggiate a chord where all the notes have different durations? I just tried entering the notes as such and Musescore won't let me. I'm new to all this, but I would think the software would allow me to write that?
In reply to "in MuseScore all notes in a… by artisland08
That's not how arpeggio notation works.
I suspect you aren't going to get a "correct " midi export from your DAW.
In reply to "in MuseScore all notes in a… by artisland08
I would think the software would allow me to write that?
Here's a bunch of notated arpeggios:
Arpeggios.mscz