Stuart Steam Engine with Anim and Description

This is a Blender 2.81 project for an animated steam engine:

The original model is from Sketchfab:
https://sketchfab.com/3d-models/steam-engine-c2ac2b3c366b4354ba34507fb16103f3
It comes with a CC Attribution License; Author:
https://sketchfab.com/takeboncog
I hope this fulfills the license requirement stuff.

The FBX I downloaded there didn't even work in the windows viewer, but it was importable in Blender ( I moved the textures folder into the source, so Blender could find it ). On export some parts were flipped but 'Object/Apply/All Transforms' solved that.

The animation was keyed in every frame and was off a bit after importing. ( The preview in Sketchfab isn't so I guess it had worked at some point. ) I replaced it with an IK-anim by this tutorial:
https://www.youtube.com/watch?v=vWjxdn1R0Ek&t=889s

In the tutorial the example doesn't loop, so I used this tutorial to make it fluent:
https://www.youtube.com/watch?v=2r0KsLYr3wA

Since I was already on it, I also rotated the exentric wheel for the valve by 90 degrees because I'm pretty sure that's how a real steam engine would work. In the end, only the bone for the main crank is animated with just two key frames.
At that point the model was ready for export as GLB and import into my Oculus Home ( where it proudly resides now :) ).

The FBX export for Sansar was a little more tricky.

First the animation needed a single root bone ( I then had 4 since the IK relationship isn't parented ).
So i added a root bone and made it parent to the rest. I also had to restrict the IK bone constraint chain to 3 or else the root bone would have started to move. This still works for GLB and FBX equally.

Second the object to bone parenting won't work with binary FBX. I read in the internet that it works in blender 2.79 with ASCII export, but 2.8 doesn't have that option any more. So I parented everything to the armature with empty bone groups and assigned every object to its designated bone group manually. Even the unanimated body is now parented with empty bone groups. I forgot if or why this is really needed. The bone groups work for the export, but the animation gets really slow within blender so its probably not a state to continue working with.

I intentionally avoid the term "rigging" here because I'm not sure if the outcome is already a rigged object. As I understood from the Blender tutorials, a Rig would have some kind of handles to manipulate and animate it. This one doesn't have that.

Third and finally I exported it with 'Y forward' and 'Z up' in the 'Translations' tab. The default setting made the whole thing spin horizontally instead of vertically. Why the default is '-Z forward' and 'Y up' is an enigma to me since Y forward and Z up is already how one usually looks at it in Blender. Changing the X and Y settings in the 'Armature' tab didn't do anything for me.

I hope you enjoy the view and that this description will help you with similar projects. And please, please tell me if you know better ways to accomplish the same thing or if I did anything entirely wrong, so I can learn from it.