from the patch notes:

Modding
Renamed the character entity type and name from "player" to "character" to make it consistent with how we call/access it in all other places.

this caused Sea block to prevent loading the game.

You can fix the error on startup by manually changing it but when in game it also produces errors with other things (inventory access for example)

Witch version of the game does work with this mod pack?

I can run it on 0.17.34 with no trouble and a few other QoL mods.

You can fix the error on startup by manually changing it but when in game it also produces errors with other things (inventory access for example)

From FFF #293:
"Another problem is in the naming of some 'defines' (constant values exposed for Lua scripting). If you want to access a characters main inventory, the value was called inventory.player_main. This makes it sound like it gives the main inventory of the player, but no, it gives the main inventory of the character. If you are in sandbox mode, using inventory.player_main will not give the correct inventory, you will need to use inventory.god_main. "

Seems like they changed how inventory is addressed.

Seems like the mod got an update, I hope it fixes this issue.

Edit: Yep, it does.

Thanks to the author!