Made it to step 5, xLODGen, Generation, Terrain LOD Generation. After running xLODGen from MO2 executable drop-down list, I do not have any options to "select all worldspaces" or to tick anything like it is shown in the examples. All I see is this:
I think I did the Terrain LOD preparation correctly, but the link to forum download was a bit difficult to follow; couldn't tell for sure if xLODGen beta 83 based on 4.1.3g link at top was indeed what I was supposed to copy into (TEMP) - SSE Terrain - Tamriel - xLODGen mod folder in MO (guide step 1 says to download SSE-Terrain-Tamriel.esm, didn't see that so I went with the mentioned xLODGen beta link at the top).