If you want to use the same uv coordinates than Mecabricks, you can use the elements found in the "Blender Addon Pack" folder. These are the parts that are used by the auto replacement function of the Blender Advanced Add-on. Both products work together.
I am working on a massive update for the Mecabricks system which will also lead to the rework of all products to make them compatible and even more integrated together.
The workflow to get custom decorations in Blender, even applied on HD elements like the minifigure, will be quick and easy.