I don't think the fall in revenue is much to be alarmed about....

I don't think the fall in revenue is much to be alarmed about. This explains a big part of it:

"As foreshadowed, sales also reflect a reduction in sales of consumables and accessories to GE Healthcare of approximately $1.8 million, mainly associated with GE inventory holding management. First half sales were $30.0 million a reduction of 4% compared with the prior half (2% in constant currency)."

Note that under the new agreement which starts from 1 July 2019, rather than GE Healthcare selling consumables and accessories, NAN will be cutting out the middleman (GE) and selling it straight to Trophon users. This will result in a "material increase in sales of consumables and margin". (Really looking forward to see what this material impact will be).

In the meantime, from now until then, it may also mean GE Healthcare will be running down their inventory in consumables which results in less sales.

More concerning for me is the slowdown in growth of the install base. The addressable market I last recall seeing in a presentation was 40,000 units in North America. Still a long way to go, and I don't think we should be at the point where there should be that much of a slowdown, so hopefully this is just another bump in the road. We've had a few in the past from quarter to quarter so I'm happy to give the company a bit of leeway on this and not be too concerned.