Which files to keep and which ones to not?

I have already tried uploading and rendering my map multiple times but I think I know what the problem is. If someone who knows how to do this can confirm my suspicions though, that would be lovely.

My map's directory looks like this:
data
DIM1
DIM-1
players
region
spout_meta
level.dat
level.dat_mcr
level.dat_old
session.lock
uid.dat

I know I have to keep the 'players', 'region', and 'level.dat' files but are the other ones necessary? Are any of them causing the problem? Which ones do I delete and which ones do I keep?

Note: I have read the post about the .mcr files in the 'region' directory and I have already deleted them. I'm just wondering about the other files in the map's main directory.

Thanks!

The other DIM1, DIM-1 may cause problems.

The world will be rejected if there are multiple level.dat files stored inside the archive.

The other DIM1, DIM-1 may cause problems.

The world will be rejected if there are multiple level.dat files stored inside the archive.

So do I only keep the level.dat file or do I also keep the level.dat_old file like in the help video?

Thank you for the help!

Nevermind, I figured it out.

Thank you for the help!

What did you change to make it work? I am about to upload a 5000 block world and don't want to waste the servers time with errors.

my files look like this (It's a new map with no .mcr files)

data
DIM1
DIM-1
players
region
level.dat
level.dat_old
session.lock
uid.dat

When I tried to upload with about 1000 blocks discovered I couldn't get it to work....definitely don't want to repeat those errors with this large of a map. Thanks!