How do I import a model into RealFlight?

If I already have a 3D model of our aircraft, how do I send it through blender and into realflight? Is 3DSMax required?

Is there a good guide I can follow somewhere? I have found all the knifeedge pdfs and documentation-but when you have limited 3D modeling experience I’m not sure what to make of it.

Another question- How long would you say it takes to get a model into realflight if you had a good 3D model of the aircraft already?

Thank you for your time.

Is 3DSMax required? yes