The CRS is announced as a smart router switch. ITs not a pure switch. To use a router to switch, you will find odd config, and or strange setup.
A routeros device is in my opinion a really good layer3 product, but far from a full l2 product. l2,5 (MPLS) Is the way to go, to have performance in routeros pushing traffic between 2 interfaces.
To have vlanx from interface y, to interface z, and have 100% performance, stop using a router device. Use a switch.
This is the same in cisco, juniper, extreme etc. Eatch product to the job its made to do. A tractor is nice on the field. But maybe not so good at the highway. But still working. A ferari is good at a highway, but what you want to use on a field. (Was it Volvo, that is ok to both??
To use vlan in mikrotik, You have to think a bit strange. In a switch, its most liekly the switch make a internal "bridge" the first time a vlan is added. After adding vlan y to port X, you can just put it (the vlan) to wherever port you want, and have it out here. In Routeros World, You have to do it manualy. Fist tag it in, tag it in a bridge to connect to another port, and finaly, bridge it to the interface it self, to have it as access, or bridge the same vlan on two interfaces, to have it tagged.