Here are the steps that I did:
1) Exported the model made in sketchup into an obj
2) Used NW4C tools to export the obj into cmdl
3) Used CreativeStudio to export the cmdl into bcmdl
4) made collision from bcmdl
5) imported the collision and bcmdl into "FirstStepASideView.szs"
6) Added the object to "CreatorClassNameTable.szs"
7) Made the level
8) Imported the byml into "FirstStageMap1.szs"
9) Moved "CreatorClassNameTable.szs" to /SystemData
10) Moved "3dltest.szs" to /ObjectData
It worked! Textures for my walls were black, but that's whatever. I found out what my fatal flaw was when trying this previously: I didn't put "3dltest.szs" to /ObjectData, instead I simply put the byml from "3dltest.szs" into "FirstStageMap1.szs". The video tutorial didn't exactly clarify, but maybe that was just me overlooking it. Honestly, the setup was harder than it should have been, but fortunately enough I got it working and I plan on making an in-depth tutorial once I get the hang of it where I make the model from scratch up to showing it off in game.
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