Well to answer your questions.
1. There is NO learning curve on a Lei the only thing that is a bit different is relaunch the rest is exactly the same on a LEI. Some companies (the only one that comes to mind is slingshot) is a atl or all terrain launch which actually backs up the kite just like a foil and then one brake line flips it. Otherwise a 5th line system you get it near its back and pull one side kite flips to the side then launches. I guess the other thing is how to hookup a lei in the wind.
2. Are you comfortable in your harness yet? Meaning can you leanback and put more tension on the kite? Really all it takes is dialling in on your right and left windows oscilating your kite hard in light winds and edging hard on down strokes and easing up on up strokes. if the wind is heavier just set sail and fly one side and lean back bend your knees and tell that kite where you want to go. Sounds like you're still at the stage were maybe the kite is pulling on you and you (go with it) Very common until you get to the stage where you put the kite exactly where you want it and hold it there indefintely. typically i start high then once moving set low and pull hard against it with your body and rail up wind. Also if you're in too light of winds it will be nearly impossible to go up wind the kites have ranges that work best for upwinding.
All i've heard and experienced thus far is edge to boost edge to upwind edge, edge, edge. It will come and on snow i think it will come faster than on land. IF you haven't got on a buggy yet if you get to try one you will see what i mean almost instantly cause buggies have the least amount of resistance next to ice skates and roller blades. You almost can't fly the kite without going upwind to some degree cause if you fly too much toward the kite it will for surely stall.
take a peek over your shoulder when getting on your line then start shooting your board that direction kite tensions up even more and although you may move slower you will be going upwind.
In nuking winds keep the kite high get momentum and you can virtually go on a straight line up wind.
Also higher aspect and more performance kites will fly faster in the wind window allowing you to leave the beginers behind on a upwind race

I love the wind and I love getting HIGH on air.