I have a solution which is working for me so far.
I have a Venu watch and a 1040 Edge cycle computer.
Before I start an activity on my 1040 I switch my Venu off. When I finish my ride I then sync my Edge to the Garmin Connect App (via Bluetooth) before ending the activity. This allows Intensity Minutes, Calories and HR data to successfully transfer across to Connect. I then end the activity on my Edge and then sync it again to allow all the other ride data to transfer across (mileage, time, speed, etc). I then switch my Venu back on.
Hope that helps, please let me know how you get on.