Not much done today, I loaded up the game to see what needed doing and noticed that one of the checkpoints wasn't labelled properly, so I changed that to make it work. I also prevented the game mode from saving gold except on dedicated save points because the gold wasn't being saved between levels and I already knew all the variables were being reset to 0 every time I opened a level. I also added a hovering arrow above the level gate to make sure players know where to go. It looks like this:
I can't remember if I did anything else today to be honest, but as I was swapping out an old broken collectible item for the new one, I somehow broke something else and now a new save is created every time the game opens for some reason, so the opening text never shows. It also means that I load in from the same place each time regardless of any checkpoints I've passed.