Good afternoon @spacehitchhiker42,
The easy way to use the AIC+
The AIC+ were originally released to allow Micros and other devices to communicate on DH-485.
That said, they are truly just 232 to 485 converters and can be used for pretty much any serial communications.
I've even had networks of third party devices on them using ASCII.
That said, the simplest way to get your Micros talk is to use DH485 and set all devices to the same baud rate but unique addresses. Use 19.2K on the AIC not auto.
Insure the AICs are powered, and the network is wired per the manual.
Then have one ML1200 read from it's own N7:0 (source) and write to the others N7:0 (destination) every second.
If it's working you'll see the AIC lights flicker every second indicating it's working. To see this in action check out my video below:
Now onto your PC - sadly, you may not be able to get the AIC+ / DH485 driver to work on your PC, especially through a USB to Serial converter since the heartbeat is too fast. This is why you can't use DH485 with Rockwell's own 9300-USBS.
Using the AIC+ with DF1
As far as setting up a DF1, as you mention you have to use Half Duplex as Full Duplex is only point to point.
While it should be possible to set one Micro as the Master (some Micros can't be a master) and Linx and the Other Micro as slaves, it's quite complicated.
The best documentation I've seen on doing this is in Rockwells "SCADA" guide which you can grab from their literature library at AB.com.
PS - If you have to get the DF1 half duplex option working and need help for a small fee I can create proof of concept for you
Hope this helps,
Shawn Tierney, The Automation Blog