There was a section I wanted to repeat, so I did the usual. Instead of repeating the selection, it stripped out every other note and left the same region selected (just with half the notes now). Nothing was pasted into the measures following as should have happened.
Exact same thing happened when I tried to copy the region, select the following (empty) measure, and paste. It looked like it pasted into the same (already selected) region, and ended up with every other note gone. This is the the Tracks window.
As I tried to figure out what was going on, I discovered something else: dragging a selection from one measure to the next leaves behind notes! As in every other note from the selection I dragged, is left where I dragged it from. Even dragging up or down to other notes does weird things, just not the same weird things.
Anyone experience this, or hear of it, or have any idea what is going on?
Here's an example of the "Repeat" thing. The image on the left is the original selected region, the image on the right is what I end up with after using the Repeat function:

And in this image, the one on top is the original selection, the one on the bottom is the result of dragging one measure later. It looks the same whether I drag in the Tracks window or the MIDI Editor window:
