Shifting down problem with roadlink
First things to check would be cable friction, making sure your b-tension screw is dialed to get the guide pulley as close to the 36 as you can get it without rubbing, and lube pivots. Your cable tension itself could also be on the high side. A directional chain going the wrong direction may also help cause it.

Hanger alignment could contribute too. Just because you put a new hanger on doesn't automatically mean it's perfectly aligned, sad but true.