Unpickable 'grand opening' level in practice mode

[Poobslag]

The level select for my game says I've completed Cannoli Sandbar, but there is one unpickable level 'Grand Opening: Merrymellow Marsh'. I'm pretty certain I've completed this level, because it unlocks the following regions which are pickable.

saveslot0.json

[Poobslag]

I think this stems from two bugs -- firstly, when you skip a region with a cheat code, it doesn't mark the boss or intro levels as played. Secondly, when you replay a region it never gives you the boss or intro levels as regular choices.