Can I mix & match different chainring brand/model? I want to change my 36 Race Face Evolve chainring (in a 22/36 setup) for a 32t. I've found a "cheap" Race Face Turbine 32t. Will it be compatibile with the 22t "Evolve" chainring or I will get shifting problems?
Should be fine, if the new 32t ring is made to be used in a double or triple crankset then your gold. If it is made to be run independently in a 1x drivetrain (Such as a narrow/wide ring) then it will cause shifting issues. 

The larger of the two (or three) rings has shifting ramps and/or pins that help guide the chain up during shifting. If it is made to be used in a multiple ring setup then these should be present, generally they rings will list what type of setup they are intended for as well such as 1x , 2x or 3x.

The other thing to check to to be sure the bolt pattern (BCD) is the same so that they will bolt together. You may also consider getting a new chain at the same time if it has been awhile.