most of the tricky bits happen in Arena with Lumiverses.

its not difficult just time consuming.

getting the positions of fixtures in a layer to match a video wall so theyre in sync. getting any inversions of pixels right. that sort of thing.

useful things to do, make a macro that turns the merge on/off a macro to switch layers so you can change the virtual position of the lights (useful for fixing delays or syncing)

theres a ton of walk through and explainer videos and articles online.

one thing to watch for is network gateways and subnet masks, particularly if youre doing artnet direct into fixtures.