In Resolume, make your pixel mapping like you’re used to. The standard rules of pixels maps apply, i.e. each slice should live in its own little area of the output. Aside from that, you can use both regular and polygon slices, and there is no limit to the resolution of the slice, the resolution of the output or even the number of outputs.
To be fully compatible with capture card workflows, the Slice Importer works with the output map.
Once done, hit Save and Close or choose Save from the drop down to save the output setup under its own name.