SMAPI: multiplayer save file issues please help!

After the multiplayer update went live (after playing the beta with minimal issues), I updated SMAPI and checked the Unlimited Player mod I'm using is up to date as well, but trying to load previous multiplayer files goes to a forever "loading..." page that never goes anywhere, sometimes crashes sometimes I just kill the program. Single player files seem to be working okay.
So far I've tried:
- restarting computer
- verifying game files
- uninstalling the mods
- uninstalling and reinstalling the game with no mods
- reinstalling fresh SMAPI by itself and then Unlimited Players
- running the XNA redist.

I noticed the red text and error log on the SMAPI box but I don't know enough on how to fix what's wrong. Error log: https://log.smapi.io/ddtQ9VZx

Any help would be much appreciated!
(Edit: using Steam version. Windows 10.)

 

@NightmareWriter There seems to be something wrong with the save file. Can you attach a zip of your save files (Dakota_187121168 folder) here?

 

@Pathoschild Thank you. I was worried that could be the case... I think I did the zip file right?

 

Yep, that save is corrupted. Here's a working version (though you'll need to replay the last day).

 

Yes! Thank you!

I'm not getting any red error messages on SMAPI anymore and the save loaded quickly without issue
Do you have any tips for preventing this from happening again?

Thanks again!

 

@NightmareWriter I'm not sure what caused that; it might have been a fluke (e.g. game crashed just as it was saving). I wrote a mini-guide for fixing saves though, if that helps.