Bluetooth GPS Provider and Tasker 
To start or stop the service via a Tasker task you can create a new task in tasker with the following settings:
Use "Action Category" "Misc".

Choose "Action Intent"

Enter "start_btgps_provider" for a task that starts the service, enter "stop_btgps_provider" to create a task that stops the service.

As the "Target" choose "Service"
Please note that it's currently very important to make sure that all the preconditions (allow mock locations = on, bluetooth = on) are met before starting the service!