We switched to the spare slow controls computer that is running Windows 10 IoT Enterprise LTSC, 21H2 (OS build 19044.4780), and the most recent TwinCAT 3.1 (4026.19.0). This TwinCAT version uses a packet manager and has changed the install directory to C:\Program Files (x86)\Beckhoff\TwinCAT. It supports Visual Studio 2022 and the new Altium workflow. 

One new "feature" is that the PLC boot project needs to be activated in a separate step (previous versions would do this automatically after a build). We updated the install scripts to accommodate this.

We also tried a new TcIoc that was linked against EPICS 7, but it crashed during SDF restore repeatedly.  We reverted back to the previous version linked against 3.15.9.