Dear Troels,
Finally I completed the PURIFI-6R speakers for my living room. I'm not totally happy with my woodwork, I don't have a table saw and I had to use my plunge saw, which is not ideal for precision and reproducibility. Anyway, as my first project, I think it is good enough.
As you can see from the pictures, I put the port of the back and the midbass crossover on the bottom.
I connected the speakers to my miniDSP SHD streamer/preamp followed by a DIY amp with the hypex NC400 class-D modules (so more from Bruno Putzeys). Still have to perform the room measurements and equalization using the DSP and DIRAC that comes with the MiniDSP. But I'm already very very happy with the result. 
So many thanks for the design and suggestions. Next will be bigger!
With my best regards
Roberto