Hi Troels,
Thank you very much for all your help and patience with my many questions during this process. I had no experience with woodworking, and yet took on an quite ambitious first project and on top decided to start making modifications to it. So perhaps you can imagine that it was quite scary hooking them up for the first time. They had cost me a lot of time, effort and money, but I'm pleased to say it was all well worth it. 
The main modification I did were an extension of the cabinet, losing the need for stands and creating a separate compartment for the crossover. I swapped the port tubes for a single slot port. And I also increased the depth to maintain interior volume as I had used 24mm Baltic birch throughout.
Regards,
Bartosz