Hey Japanson!
I've seen this issue pop up from time to time, where the saves don't sync automatically.
If you still have your 0.7.18 folder, your saves should still be there (AHITR/Game/Saves) and you can transfer those to the newest version.
If not, there should be a back up folder in:
AppData\Roaming\RenPy\AHouseintheRift
Hopefully this helps!