Huge milestone reached!
I also made a version 2 of the Nano 8088 board because the compact flash connector wasn't available anywhere. Fortunately, once assembled, the board worked! The compact flash doesn't seem to work yet. Once this works, I'll try to push my files on github to the same project.

Meanwhile, I assembled 2 PCBs from Microcore Labs: the MCLZ8 and the MCL86+. That give alternatives to my alien probes for testing. At least I don't need to debug the 8088 anymore.

The next test was to plug the BBTC on the passive motherboard along the Nano 8088 v2. Unfortunately, the card blocks the bus and nothing works. When I removed it, the Nano 8088 works normally.

Next step will be to whip out my Alien Probes. Time to analyse this more deeply!