CNC - Fusion360 STL files

Has anyone been successful with Fusion360 importing and setting up a STL file for carving?
I downloaded a STL file from Thingiverse and imported the file into fusion 360, I was able to get to the machining process. Then repeated some of the steps provided in the (Snapmaker academy). Produce the *.nc file

  1. First issue, my Snapmaker does not see/recognize the NC file from the USB drive. I had to rename to *.cnc
  2. I setup the material, aligned, set boundaries fine. Run boundary check, everything looks good, then
  3. I start the job, the machine begins to go to the lower right hand corner and goes outside of the boundaries, then begins to move up at which point hits one of my brackets.
    If I set the boundaries, why does it do this? Is there a way to control it? In my second test, I tried to cnc a very small item (50mm x 50mm), the board I use was much larger 10"x10", but still had this issue. Is there anything in particular that I’m doing incorrectly?

Have you installed and are using the post processor for SM?

I assume there’s a problem with your settings in setup for stock and or work origin.
Need to share your settings in fusion (screenshots) and gcode.