Back and forth

This is my first post to this forum even though I have been reading it for some time. Normally I can find what I am looking for, but this one has me stuck and I would like to learn it.

How can I have a MC play backwards and forwards using buttons to navigate to specific frames in the MC. It would be easy enough to gotoAndPlay or stop, but I need it to play the MC to new frames.

I have included the file if it helps anyone to understand my vague description.

TIA if anyone can help me.