Lloyd when you turn on the Central Heat Control, and adjust the thermostat do you hear the Webasto start up? It will sound like a small jet engine, very noticable.

If you are not getting airflow, I would assume your fans intakes/outtakes are dirty and may need a cleaning. If it's not hot, then the webasto may not be running. Note, the Webasto will not run, IF the water in the system is already hot enough, like if you've been driving.

Ray

ps: I may be wrong, but the switches you're describing by your right leg are for the A/C system. I don't believe the heating blowers are affected by those. I don't remember any controls on the heat blowers. They didn't blow real hard, but if hot air is coming out, you don't need a ton of force.