Renderers disappearing when switching to flight [fixed]

[Nertea]

I have a part, worked fine in KSP 0.90. Now this same part will show up just fine in the VAB, but will have some (not all) of its meshes hidden when moving to the launch pad. Reverting to the VAB does not replace these meshes unless the part (or its parent) is picked up.

Anyone seen this before? Initially I thought it was linked to landing legs, but I've now cleared everything beyond the bog standard part definitions in the file, and it still occurs. I've tested

• Reexporting the part repeatedly
  
• Changing shaders down to simplistic KSP ones
  
• Removing colliders
  

All with the same behaviour.

- - - Updated - - -

Well, like anything, all you have to do is give up and ask for help, then you'll figure it out.

For those interested, apparently now having a part tagged with WheelCollidersIgnore in Unity results in weird issues with its renderer, and selectability.