I've been playing the muluna mod and have wondered about this one as part of the pack the entire time. I'm not at the interstellar science pack yet but have not seen any reason why I would need a tile upgrade planner to play with the mod

There's a tile called the "Low density space platform foundation" in the Muluna mod, unlocked with interstellar science and carbon fiber. This tile is a strict upgrade from the regular space platform foundation, having half the mass and twice the HP. Without the tile upgrade planner, it becomes impossible to quickly upgrade a space platform to this new tile while keeping the platform's original shape. This fork is necessary to add this new tile to the tile upgrade planner's default list of upgrades. I feel that if I don't forcibly bundle this mod with Muluna, I would be required to answer questions about how one is supposed to upgrade a space platform to the upgraded foundation.

Oh! That makes a lot of sense. For some reason, I had thought that the low-density space platform foundation unlock was just an alternate recipe for the standard space platform foundation.

Thanks for explaining :) Cheers

Oh, that's what this is for... I tried using it for swapping Alien Biomes ground tiles and it violently crashed - then I forgot it even existed.