The next update has millions of changes, this is how the save compatibility works. It converts old values to news when transferring a save from v0.1.2 to v0.1.3, so the save works.Or maybe, I'm no dev on Ren'py or anything so I don't know how reasonable that is, but have a way for the game to check the status of a save to then convert it to the next version.
Some kind of file that would remember what perks/money/achievement a save has to then import it back on the new save.
I know some games do that, let you import saves from prequels to continue the story while keeping the same choices made in the previous game, but I don't know how feasible that is here.
When I try v0.1.2, normally, I get a crash screen saying what was the problem and etc. So I can fix it.
But when it's about Renpy 7.5 to Renpy 8.0, it just gives a crash error that it's basically impossible to fix, it's like every single line of code works differently.
It works perfectly when you start a new game, but not when you start from an old save.
Also, remember that most games that have that thing of importing saves are pretty simple in terms of code. They just transfer values like "evie_affection", "hasThePlayerSeenMaria", etc. Small variables/tags. So they will mostly have 0 errors.
In my case... well...
THERE MAY BE A FIX transferring from Renpy 7.5 to 8.0. But I don't feel like going through 177 scripts with millions of lines of code to check every single stuff, not at least right now, where time is being... quite demanding.