REL owners, how many clicks on your gain and crossover

I just bought a couple rel subs and wondering where others are setting their dial. I know everyone’s room is different but just curious, if you would like to mention room size and where you place it that would be nice too.
 

I’m using monitors that go down to 40 or 42 in a 12x14 room and have subs right behind monitors on the inside for now, only received subs yesterday. So I’m still breaking them in, have no clue how long subs take. 
 

Place I bought subs advised to just run one hot wire(red) to amp yellow is not being used. Is this right am I losing gain or power by loss of yellow wires gain into sub. I’ve never used a sub for 2 channel it use to be taboo. Oh well I’m in now.