I don’t know that we can be more clear about ignoring reflections, find areas of detail that don’t have reflections on them that move on the same plane you are trying to track and only draw your shapes around those areas. Can you let me know how you’re having trouble with that so I can be more specific?
For an object going offscreen, while creating the track you will not be able to get the spline offscreen and still have that shape track, because the shape is where Mocha looks for the data to track. You can delete keyframes when your track is complete to get rid of any movement you used for offset tracking or you can create a new shape and link to that track if you like. If you can’t get good spline placement for the object as it moves offscreen and have no object moving similarly, you will need to treat the offscreen movement like an occlusion and use manual track to create keyframes of “good data” on either side of the offscreen movement and then track backwards and forwards into the offscreen movement for best results.
Unfortunately, it is hard to create demos that work for every scenario you might encounter and we have to rely on extrapolating information to vary our techniques for production. I can see if I can find a challenging track to showcase this data, but you can also check our webinars on track troubleshooting for difficult shots (the sound on Webinars has historically not always been awesome but the data is useful).
Please let me know if you need clarification on these techniques.