Indeed. I know nothing of operating Rotax engines but having observed them in use I can see they might require very different handling to the old iron. The shutdown procedure for the Gipsy Major, for instance, calls for idle throttle, both mags 'off', then throttle fully opened.
The reason for the fully opened throttle is that if there are glowing carbon deposits in the cylinder to provide an ignition source, the engine might 'run on', albeit lumpily. Opening the throttle wide at such very low RPM (it's after the mags have been cut) reduces the vacuum in the throttle venturi to the extent that what is drawn into the engine is mostly if not entirely fresh air, so not combustible, and the engine stops with no tendency to run on.