@yukinoh1989 Append the model in 2.7 and use the upload plugin. That simple.
Press 5 on the numpad to switch between ortho and perspective. Why would you want to only work in ortho, though? What possible discrepancies could crop up between ortho and perspective? If you worked strictly in ortho, then uploaded to a platform that uses perspective for viewing, how would that affect how your model is viewed? Unless that’s your intended view (isometric styles, for example) I would think about how that would affect how your model is viewed.
I’ll get you those annotations soon. Caught up in other work.