Question, will I'll be able to transfer my Demo save to the full version?
I'm honestly not certain on transferring a save from the 2020 demo to the full version. ^^; I've made some balance changes between this demo and the final demo I'd like to release, but not too many event flags were added between the current demo (2020) and the final so I'd say your save will probably transfer well enough as long as you don't retread too much of Bravery. (I think the worst case scenario is some flags on meeting Siza were altered a bit)
Transferring saves is something I'm being very mindful of while working on the final demo. My intention is to have saves in that demo be able to transfer to the full version seamlessly.
I did design the segment of Bravery in 2020's Demo to be easily replayed once the player knows where everything is in the event that that area would need to be replayed upon the full release, but I'd definitely prefer to have a save from that transfer as well as it can!