That asov is designed for systems with pressure tanks. Not likely to be the issue, but I can't say for sure.

I'm still saying that the tubing is wrong. It looks complicated, but it's really not.

housewater>prefilter/carbon blocks>asov in>asov out>ro membrane in (the single fitting in the screw on cap)>membrane>center fitting on membrane house goes>asov in>asov out>di resin. The offset fitting on the membrane housing goes to your waste line.

The flow restrictor should be in your waste line as it exits the membrane housing. It's a vital piece of equipment, as it creates backpressure so that the membrane can function properly.

Can you get a better pic of your asov where it's marked in and out. I can only see the upper part of it.