Driving on to Levelling Ramps

I bought the three stage Milenco ramps and in about 5 weeks of touring have only needed to use them about three times but being a complete novice I seem to make a hash of it every time. Handbrake on, first gear, lots of revs followed by burning smell (clutch plates?) and eventually up to second level. Top level seems too precarious and the ramps need to be VERY secure with no twisting etc. to risk it. Also some of the plastic is already breaking away so they are not as tough as they are made out to be.

Am I doing anything wrong? Is there a better system?