If you are in the top hole of with the jib, you will easily oversheet the jib and close the slot.
Also you want to sheet in quite hard on the main, if the leech closes pull some cunningham to open it again. If you just easy your mainsheet, you loose all the benefit of a puff.
Set your sails and have someone sail behind the boat. That's the best way to see if your leech is closed or if the slot is not open. Adjust and mark so you know your benchmark.

Also foot off enough to get speed. Apparent wind will change and you will be able to steer up and sail high with more speed.

If the water is flat I would have less rotation, flat water is a flatter sail as well.

The infusion is a great boat but you always have the feeling on the boat you are doing well (so I find it less responsive in that way). So I wouldn't trust too much on feel for this in light stuff.

On the downwind I would say easy the halyard of the spin a couple of inches and play a lot with your weight (for and aft; up and down) so you don't have to steer too much.

Just some ideas.

Gill