Any more hints on level 9? The ones given don't help me to figure out how to even start.

"Flip-flop", like in a circuit? Those could do a myriad of things to encode the message.

"the second word" .. is the decoded message the first word or is it refering to 8bit words or something?

I think you're trying too hard on the "flip-flop" clue.

I'm very confused, I've solved the cipher for level 4 but I can't get to the next level by typing it in? Ahhh, you just type in the last word. Solved.

For what it's worth, the level solution hashes in github are pretty googleable. (Easier to google than your name, I found!)

But why would you want to?

Marvin isn't your name.. It's Aakash? What the hell!