Avantgarde Uno Nano suitable for small room?

Yes, the Unos's will work beautifully in that room. Close to the side walls,with appropriate toe-in and about 3' to the back of the speaker from the rear walls. Sitting position against the rear wall. Near field magic...especially with the Lamms.

Yes, as long as you are able to sit at least 10 feet away from the speaker to allow the drivers to properly integrate.

You will love the Lamms with Avantgardes. The room sounds tight but doable; the key as Brf noted is to sit 10+ feet away, but while also preserving width (tweeter to tweeter) of 83% of the distance from each tweeter to your respective ear, so to sit exactly 10 feet away the centers of the tweeters should be 8.3 feet apart. This will place the outside of the mid horns very close to side walls. Luckily the speakers are very directional so placement near side walls is of little concern. Good luck!