Bayne, don't know what you read that led to a LFE+Main setting, but if the speakers are set "Small", that doesn't have an effect. All the frequencies below the crossovers set(including for the mains)are sent to the sub and it handles those plus any LFE that may occasionally be present during movies. The LFE setting is the appropriate one. The "+Main" is meaningful if the mains are set "Large" and are playing full-range. The "+" setting would then duplicate the low bass from the mains in the sub and isn't generally advisable.
For two reasons the crossovers set at 40 or 60Hz should be raised to 80Hz: giving the EP500 more work in the frequencies that it handles best, and since Audyssey has higher resolution in the sub channel, it equalizes it better than it would if those frequencies were in the speaker channels. The QS8s at 100Hz is apparently the best setting for their location, and should stay at that setting.
