Glad it went well. What fasttruck said.
The air leak under the dash is not normal. Use some soapy water or 'bubble stuff' and a small brush to go around each fitting under pressure. Might be loose, might do with some teflon tape, or you might have a rotted hose to replace. You want to fix that so you don't overwork your compressor.
If the bucking is going forward, make sure you're in 1st gear and don't start out in 2nd, ever. There are plenty of arguments on here about that but I'm convinced by that advice. On the flat, you should pretty much be able to pull out in 1st/900 rpm without touching the throttle. Don't dawdle. Engage, move, and get off the pedal. Upshift at the proper time. I keep my left foot on the floor between gears, but that's how I was taught to drive a car back when they were pulled by mules.
Let us know.
Steve