From my testing, it appears there is a lacing issue inside the node that is causing the nulls. When I testing it with the FirstItem node for room and view, it works without an issue. @jean do you have any information?
I am not sure if it is an option, but I would also recommend that you update Dynamo and/or use 2.* version so you can update to the latest Quasar package as well. This may resolve the issue since the v.0.2.0 is several updates old.
Also, if you view the GitHub for the package examples, you can see the video for this shows a single level being supplied and not a list.