Like some one said, too much is happening in the first installment
and it's too disjointed.  Okay, first MOussse is declaring his
love for Shampoo and he's rejecting her again, and then 
Akane's kissing Ranma and he's beginning to like it and 
so is she.

That's when the average reader's mind goes, "What?!?!  Could you bakc
track that a little bit?"

Luckily for you, I'm not the average reader.  I think that to fix this,
you could have Mousse wondering about how to win Shampoo's heart
for good, and then cut away to either Ranma or Akane wondering about
their "relationship".  Then have them get into a fight that ends
with them in a compromising position, but no one makes a move.
*THEN* you tie the two halves of the story together by having
both Mousse and Ranma realize... whatever you want them to realize.

Foxtrot the FUrryous