I have the same problem... I followed the video tutorial and surprise surprise no combat, I can't even trigger it *without* an enemy as there doesn't even seem to be a trigger function for this, you can only test when combat ends, but not make it actually start.... ;/
I have seriously no idea how Larian even got this working in their example mod, because from what they shown they certainly did NOT create a new mod. What they work with is clearly using modified assets from MAIN that we don't have. (otherwise their "goals" would not build without 70k errors and nothing would work without major fiddling). Or in essence, their tutorial uses assets we don't have access to.
At this point Larian should probably give us their tutorial assets before posting other videos, because while combat works fine if mod is dependent on main (no surprise) it works absolutely not at all for some reason when doing it in a new non-dependent mod. And as you say, there is no (obvious) way to import the main scripts without breaking the build function completely.
I have asked this before and nobody seemed to know how to fix this.
And yes.. I know I could work around it by making my mod within the campaign dependency itself, and build scripts on-top of that. But that's no way to make anything, it takes forever load, scripts take forever to build if you do this...
Surely someone must have figured out how to get combat and assorted basic gameplay functions working in a new non-dependent mod?