I usually convert small to medium areas (no more than 20 area-counts in FSET, but mainly between 2 and 10 area-counts). When I use the helper I've found crashes during the process of copying the resulting images (bmp files) to the geoconvert working folder and also during the conversion itself. As a result, I've decided not to use the helper when converting areas bigger than 9 area-counts. That worked well with me.
Cheers, Ed