Regarding Pre-work: I had completed all the questions in the interview bit prework.

1. Level 3: My Interview Bit profile doesn't reflect that I have crossed level 3, I finished level-4 before finishing level-3 hence it doesn't say that I have completed level-3, in the gif I visited questions related to both level-3 & level-4. On those individual pages you can see that I had leveled up both 3 & 4.
2. Unique permutations: All my solutions were written in Ruby, I have written multiple versions of it on interview bit, all of them were timing out, this is most likely an issue with ruby execution on Interview bit, I added my solution to my github profile.