1. Don't know from your link to the Amazon ad, but it is the only input; LFE input sometimes means the low pass filter (crossover) is disengaged but I'd suggest to turn the crossover knob to maximum to start to make sure.
2. Yes when using a subwoofer set speakers to "small" which basically means I want to use the bass management feature in the avr.
3. I wouldn't recommend LFE + Main at all; you'll get bass redirected already simply by using bass management. Try not using LFE+Main first, see if it is to your satisfaction. You can always tweak the subwoofer output level in your avr to adjust somewhat. DynamicEQ I would recommend for moderate volume listening, but not Dynamic Volume.