Trying to click on quests in the quest tree (the beginning of it all) and the game fully crashes. using curse forge stand alone as source. Not sure what to do from here.

The game crashed: rendering screen
Error: java.lang.NullPointerException: Registry entry not present: gtceu:fluix_dust

Incorrect quests between server/client. Normally caused by a mod mismatch or auto-updating the pack without using a fresh install (this is how you should generally update modpacks).

Back up your save and move to a fresh install and this should be fixed