Northwoods, the transmission isn't an automatic. It's a manual, but the british nomenclature is that it's a Self Changing gear box. If handled correctly the transmission is in fact stronger than a typical gear box.
First Rule:
Don't slip the clutch, it's not a clutch, it's a gear change pedal.
Second Rule:
Don't idle stopped while in gear. That overheats the fluid flywheel (power connection between engine and transmission) and ruins your seal allowing fluid to leak out.
Third Rule:
Don't run in too low a gear for a given speed, that can over heat the fluid flywheel.
Basic operation involves preselecting a gear before you change. You can move the lever all you want. It doesn't change into the gear you've preselected until you stomp on the pedal and let back up (smartly, don't treat it like a clutch remember). Now you're in the gear you selected.
Say you're starting off. You start the engine up up neutral (gearbox) warm it up then preselect first gear (change the lever to 1st). Stomp on the gear change pedal (and let it back up) then step on the gas pedal and you're off. Preselect 2nd and when you get to near redline (the governor should limit your revs here), let off the gas and at the same time stomp the gear change pedal. If you do this correctly, you'll have a VERY smooth transition from 1st to 2nd Gear.
Downshifting is similar depending on what you're doing.
There are two ways this happens. If you're going up a hill and you're running RPM down due to the slope of the hill, preselct the next lower gear and as RPM's get to 1500 or so, stomp the gear change pedal and you'll now be in a lower gear. There is no reason to fiddle with the gas.
The other area is where you're coming to a lower speed, let the RPM fall off by letting off the gas pedal. Preselect the lower gear and as you get to the middle of the range, you can engage that gear. You can do this more peculiar ways, but you want to minimize the difference in speed between the gear box and the engine when you make the change. The fluid flywheel minimizes the impact to the system when you do this (as in all situations).