Im looking for some awnsers with my fractional rig..

Any serious advise will be appreciated.

1st...... My furler seems to have some sag in it which I'm failing to remove. I have tightened the halyard and have pulled as much backstay on as I'm humanly able which has helped slightly.
Im thinking to perhaps tighten the forestay but I worry that I will put the rig out from the original setup.

2nd...... I have noticed the tappered section of the mast bending back every time I'm falling off a wave I think, Is this normal?
Do I need more back stay? I would suspect this is putting some huge tensions on the mast section.

3rd........ If I leave the back stay tensioned overnight does this fatigue the mast?