How easy is it to recover a C3 Project?

I've slowly and painfully been converting a huge Construct 2 project over to Construct 3.

So far I've been doing it for about 2 weeks, for hours each day.

Today, I load it up to have a message pop up saying "Failed to open project. Check it is a valid Construct 3 single-file project."

Each time I save, it creates a backup, so at first I simply shrugged it off and went back to one of those.

Unfortunately, the exact same thing happened... to the next 23 backups :(

I've been using Beta 195, so yes, my fault for building a project using a beta. Honestly, in the project, all I'm doing is adding in a few things that are missing. I haven't added in any extra plugins recently. The only thing that comes to mind, looking at where the most recent working version is, is changing the pin behaviour to the new version.

However, upon testing that by changing the code then saving a new version... it again loads.

So all in all, I lost about a day's work, which kinda sucks, but at least I didn't lose everything.

Is there a way I can force the project to open so I can at least see a message as to why it's failing to open?

It doesn't make sense to me that there are 23 corrupted saves, yet zero warnings.

Unfortunately, looking back on the project, yesterday was a SUPER productive day.

Let the tedious work begin again! :(

EDIT - Looking at the error log I'm seeing this:

"Exception opening: Error: behavior type name 'Tween' already in namespace"

Not sure what that means...

I have a family called "Tween", but I have that in the working version as well.