Uber-c no bug, and the whole quest is reasonable easy to understand. [only the event of the crystal it's complex] that spark require neranda maxed. you can still exit and max her. before you end the section.
you can grind all the stat at 0. but you need to trigger all the event. neranda event reduce frigidty by 1, so you will remain with 1 point, but it isn't a problem, if all the other three stats are zero, you can end the quest.
for racism in the 0.69.2 you have all the event needed to reduce to zero, so you missed something