Each part of the house is its own element i.e porch window 1 is its own element, porch window 2 is its own element and so on.
I have yet to sequence anything on the house itself in nutcracker. The house is done completely in LOR. The trees were done superstar. The reason I drew it in xlights preview was to actually see it all play back together. LOR's visualizer is limited on how many strings of pixels you can draw in it. Xlights is not. So I do all my sequencing in LOR then convert to xlights for display preview and to add effects with nutcracker on any model I didn't like or want to add to.