Thanks for the positive feedback!
It's great to hear that the advice given here actually helps.
Try a couple of things:
First, a faster tack.....
Try keeping the clew (I know you thought it was a clue, but one's for detectives, and one it the back corner on a sail (where the outhaul attaches) all the way down on the back of the board. You cannot go forward like you are doing and have the clew/foot of the sail all the way down on the board, so try "stepping over" the mast instead of backing way forward of the mast foot.
Uphauling is really OK. Just need to analyze why you are falling in the water and take care of those issues.
As far as a beachstart, have you practiced "steering the board" by the rig.
Go out in knee deep water (whatever depth will clear the fin) and keep the centerboard all the way up. Then practice turning the board around while holding onto the mast with one hand and the boom with the other.
The back hand regulates the power in the sail, and the front hand "pushes and pulls" the board around by the mast foot.
Once you can turn the board through 360 deg. in either direction, you will have the control to allow you to align the board for beach starts (and later water starts as the principles of "steering the board" are the same.
You can start using you harness at any time. Now would be good.
Expect to get "tossed" quite a few times until you figure it out. Might be easiest to start with a waist harness as the hooks a bit higher and easier to hook in and unhook.
Hope this helps,