I added a machine using the following steps:

1. Install the secondary arcology using arcology /install /arcology:benedict
2. Add the second machine in AI2
3. Then I tried to add a module, but we timed out. Almost as if messages were not being delivered.

I tried restarting the secondary, but no change.

Then I tried restarting the primary machine, and tried to add the module again. This worked fine.