I saved my map, then went to go test it.
The lobby was normal, and so was the briefing.
However, after the briefing SC left b.net then the error "unable to load map" came up.
I tried it again and the same thing happened- so when I opened the map "something bad happened" and my map was completely deleted...

It wasn't even in the recent maps menus when you go to create a game.

Any idea how this happened? Also, how do I open the .bak data?

Probably you did something strange to the map which prevented the map to be loaded. Or a random ScmDraft bug that didn't write the file properly. When ScmDraft crashes instead of closing properly the recent maps won't be updated. This does not mean that your map got deleted, you just have to reload it manually.

In any case just go back to a working version using the "backup database" in the "advanced" menu.

Clicking on "Open backup database" causes SCMDraft to crash. I have already tried re-installing. Should I just scrap the old database and start a new one? I'm wondering if it's corrupt.

Check your ScmDraft folder if the backup database file is overly huge (2 GB). This is a known problem but there's no fix to it except deleting the file and thus restarting the database. All your backups get lost in the process.

It was 250 MB, I just deleted it. At least I have the map backed up elsewhere so I didn't lose TOO much work.
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