I have a similar but slightly different problem and I'd love some help.
I have two computers running OpenLP: a Windows 10 running 2.4.6 and a Windows 11 running 3.0.2.
My playlists, which I made on 2.4.6, are saved on OneDrive. Back when both computers ran 2.4.6 (which was until 3.0.1 was released), there was never an issue opening and updating the playlists on either computer.
Since updating one computer to 3.0.2, I hadn't experienced any issues with opening and editing the same playlist in 2.4.6 and 3.0.2. However, today I tried opening one of my playlists (which is only 21 KB in size) on 2.4.6 and it gives me an error message and didn't load any items in the service. However, when I open this service file on 3.0.2 it works fine.
Here's a screenshot of the error message I get when I try opening the playlist in 2.4.6 (there's oddly no option to save the error log, which is unusual):
I've tried opening my other playlists in 2.4.6 (I've also been using these playlists in 3.0.2) and they're opening with all the service items included. All these playlists only contain song files, a few custom slides and a few images - no video or audio.
Also, on 3.0.2, I've tried doing "Save As" to the service file that doesn't open on 2.4.6. This new copy opened fine on 3.0.2 but didn't work on 2.4.6.
Any idea on how to get this service file opening on 2.4.6? Thanks!