The saved layouts are on me, I never noticed them at the top of the Dungeon Plan screen. Good to know they stick around after a loss as well, that makes rebuilding much less of a chore. And the Teleporter makes sense now, I had no idea it was meant to show up at Rank D.
On the currencies, the reason I have not spent any is that I have not actually lost yet. Kicking adventurers out costs so little mana that I always have a big surplus, so I just eject them long before they get near the core and the run never really ends. Might be worth raising that cost, because at the moment there is no reason for me to let a fight play out, and it means I have not seen any of the unlock side of the game you are describing.
Still playing it though, I like the concept a lot.