Main Concept's DIVX Encoder? No 2-Pass Option?

I'd heard that the best H264 codec out there is by Main Concept, so while checking Main Concept's Reference... I also started experimenting with their DIVX encoder.

I was shocked to discover that if I use the DIVX Home Theater preset... that I'm unable to check off the 2-pass option or get into advanced options. The other DIVX presets are of no help since they are the wrong resolution… either mobile or HD.

I just find it bizarre that I have more advanced options in the $20 DIVX Pro codec and the free Dr DIVX, than in this $500 codec. I can't find anything in the manual. Anyone else know what's going on here?
Is there some way around this?

Thanks!