Because of some interface noise issue on the Smoothieboard, they are not recommending the VIKI or most other LCD panels that they were planning to use.
I have a RRD full-graphic LCD-12864 clone, and have wired it to the board following wolfmanjm's instructions. It works, but there seems to be a 5V power regulator problem on the Azteeg X5 Mini that may be causing it to freak out and only display gibberish after a minute or so. It was suggested to power the GLCD from an external 5V supply, but I have not tried it yet.
Wolfmanjm has the code and instructions in his github to use a small Arduino board as an adapter circuit to use pretty much any LCD with the Azteeg X5 Mini. I would like to see it incorporated onto a daughter board that plugs over the X5's aux pins, but am not holding my breath that someone will make that happen.....