i can hopefully help you with save files.
Deck variables go as long as the deck plays. resetting the deck resets the variable, but not resetting the card or going to another.
Actor variables, however, go as long as an actor lives. they only reset if "when this happens, reset actor variable to initial value". deck resetting doesnt affect them. so, if the player reaches a point, make a actor variable(from checkpoint) to 1. now, give checkpoint these rules to work: "when this collides with tag player, modify actor variable to 1" and "when this is created, if checkpoint is 1, tell actors with tag player to destroy themselves, and create the player infront of the checkpoint. so basically, when the deck starts the checkpoint will check if it is triggered and destroy the current player and respawn him here.
anyways, so i saw your"wanna become a beta tester for the cabin" deck, and i sure am good at finding bugs(good way and bad way). luckily im pretty good at coding here, and i would love to play.