Hmmm, okay, I see what the issue is. It's an interesting problem, that I don't know yet how I'm going to solve it. The game now reshuffles the presets so that they are assiged to the world type they belong to - So a Hamlet preset can't be accidentally applied to a Shipwrecked world, but your save has a preset that - as far as I know - could not be from the game, so the game fails to recognize what DLC to assign it to. Could be a mod you once installed - doesn't seem your current mods would create something like it. I'm sorry, I'll have to ponder how to solve this. * As an extreme workaround I can offer two solutions if you want to edit your world settings now, but both have their issues. 1) Open the console in the mainscreen and enter  Profile.persistdata.customizationpresets = {}
....however that will erase all your current worldgen presets. 2) Go to playerprofile.lua in the games data/scripts directory and change line 862 from
            assert(false) assert(false)
to  -- assert(false) ...that will keep most of your presets, but not the one it doesn't understand. Not ideal either, and you should do a verify game files after you succesfully went into the world customization screen once to restore the code to its original state. Again, apologies, hope this helps.
    • Thanks