I assume this issue must be some kind of user error, because I cannot make /mv import work. I am running Multiverse-Core and -Portals -4.1.0 on PaperMC 1.16.1. I am attempting to import some adventure-style CTM maps as extra worlds, and absolutely nothing I have tried successfully imports. The error asks me to run Minecraft-Region-Fixer, but it comes out clean for all the worlds I am having problems with.

All the worlds I am testing load up fine in singleplayer. In addition, I generated a new singleplayer world, and attempting to import it returns the same error about world corruption. Is this a bug or am I stupid?

I actually figured it out. I had unpacked the world as root and my minecraft user didn't own the file. Perhaps /mvimport could give a more helpful error? Either way it's not really a bug with your stuff.
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On 11/7/20, Ben Woo @.***> wrote: Anyone still having issue with latest version of mv and papermc. Also please send full error and output of /mvversion -p if you face issues. -- You are receiving this because you authored the thread. Reply to this email directly or view it on GitHub: #2324 (comment)

This works. You should notice the owner and the group of the world folder

1. Is the world created on 1.16.1?
2. Try with the latest build of 1.16.1 spigot/paper (i.e. when you run /version they say you on the latest build)
3. Try with only mv plugins installed

1. Tested with both an old world and a new one generated on 1.16.1. Both work when loaded in singleplayer.
2. Updated to the latest snapshot (git-Paper-46). No change.

Will try 3 later.

Having this same problem. Imports work fine on 1.15.2, assuming we just gotta wait for an update

Anyone still having issue with latest version of mv and papermc. Also please send full error and output of /mvversion -p if you face issues.

Alright glad to hear! Will be closing the issue then.