Hi Barry,
the simplest method would be to create a simple REST based solution to allow retrieval and update of your HANA entries, it is my understanding that the DB tunnel is there to provide the ability to do schema manipulation rather than continuous data load/extract.
there are multiple examples of this in the ESPM scenarios. They are definitely worth checking out.
A tutorial to rule them all: the epic ESPM scenario tutorials
Cheers,
Chris