If you use Jill, there is a total of 17 rooms you can even skip or avoid backtracking into. Do not get the Mo DISK. Avoid a lot of battles, as battles take time . Saving also takes time, so cut down on those. Plan way ahead, so you don\'t end up backtracking to an item box. Another thing I recommend is, buy a guide and then mark out which rooms can be avoided and what is needed to progress. Also use the gernade launcher trick.
Oh and when you are rescuing Richard, you can solve a couple puzzles in the process, he won\'t die that fast. It saves quite abit of time and backtracking.