here are some main points i found to possibly be the issue, but i am noticing it's crashing upon generating some underground stuff like the pink salt caves and lichen caves. every report changes which depending on what it crashed on i suppose, but here is a very short tl;dr:

Description: mouseClicked event handler

java.lang.IllegalStateException: Errors during registry creation

Suppressed: java.lang.IllegalStateException: Unreferenced key: ResourceKey[minecraft:worldgen/biome / galosphere:lichen_caves]

if you need more, here is the crash report:

galsosphere crash.txt

for context, this is my first custom modpack i'm making. i have learned a lot in getting it to work properly and so far so good. if i absolutely just need to go without galosphere, then i suppose i will have to. I just would seriously love to have it if possible.