Custom model don't show up in model editor or viewer?

[Traggey]

import mesh is a feuture in the model editor and not in the model viewer as far as I know. the model viewer is the correct tool to use first when importing assets as it will generate a .msh for you and depending on your settings also a .mat file(s).

Depends on what you want to do, this is fine with static objects, but you don't want a generated .msh file for an entity.