OK - I have now been able to get the sensor working perfectly in OH2.1 as well.
I get door OPEN/CLOSE at door open/close - and I get tamper-alerts as ON/OFF. The sensor also sends temperature and battery readings every 5-6 hours.
I believe the trick was indeed to install Chris’ development version of the z-wave binding; follow the directions from Chris’ earlier post in this discussion.
As directed, you need to de-install your current z-wave binding in PaperUI, download the development jar-file as Chris directed, and place it in your add-on folder.
In my installation, all the z-wave items then needed to be deleted and re-found, in order to show online again.
Then, for this sensor, you need to configure the device association groups so that your controller will get the call when the door opens. I set both association group 2 and 3 to my controller (Node 1). I then set my configuration parameters like this:
1: closed when magnet near
3: 2nd group “ON/OFF” sent as secure
11: Switch after opening and closing
12: 99
These are my items:
Contact xDoor "Door [%s]" <contact> { channel="zwave:device:36f36c45:node6:sensor_door" }
Switch xPowerAlarm "Power Alarm [%s]" <switch> { channel="zwave:device:36f36c45:node6:alarm_power" }
Switch xTamperAlarm "Tamper Alarm [%s]" <switch> { channel="zwave:device:36f36c45:node6:alarm_tamper" }
Number xTemperature "Door Temp [%.1f °C]" <temperature> { channel="zwave:device:36f36c45:node6:sensor_temperature" }
Number xBattery "Door Battery [%d %%]" <energy> { channel="zwave:device:36f36c45:node6:battery-level" }
It took me a bit to figure out how to get the development version of the binding installed. The reason was that I needed to install the serial feature (mentioned in Chris’ post) and for that, I needed to log in to the (Karaf) console, which I had never done before and therefore needed to google around for directions.
Finally - I found that I had also managed to install the sensor in the wrong way; make sure that the small magnet sensor meets the main sensor where there is a marking on the side of it. It is described well in the manual for the sensor - but somehow I had failed to read that 
As said - everything is working well now, and I am ready to install more of these sensors.
Only worry at this point is, that my battery says 55% after two weeks usage - but I also think that the battery was already a bit worn as I got it - so I will keep an eye on it for now and make sure I have some spare batteries around. The manual says up to 2 years battery life…