New t2240 smart flow owner, few questions

Hi just picked up a T2240 smart flow trainer and have a few questions.

I also have a edge 530 plus speed and cadence sensors on my bike plus hrm pro.

1   I've tried setting up everything but each tacx exercise doubles up on Garmin connect. Tacx workout won't show heart rate but edge one does.

2.  Edge keeps telling me to do a power calibration but this ends up failing with code 65535. What am I doing wrong?

3.  If smart flow can do my cadence and speed is there any point in being connected to the bikes speed and cadence sensor?

4.  Is there any pages or YouTube video to show how to set up the tacx with edge so it all talks to each other?

Thanks in advance.