Welcome to the forum...
I'm curious if anyone else is using this ATC and if so, what compressor are you using. Most compressors have their SCFM rated at 90psi and pressure typically has an inverse relationship with volume. So if I get a compressor that just meets the requirements at 90psi, at 100psi the same compressor likely will not meet the requirements.
- Compressor: You will need a standard shop air compressor capable of 100psi output at 5-6cfm (1-2cfm if no case pressure is used). The air supplied to the spindle should be clean and dry. Different regions will require different air preparation, but a 5 micron filter is recommended at minimum. It is critical that the air pressure supplied to the machine is not compromised by use of other tools, etc.
I also purchased an avid CNC pro, but have not had a chance to assemble yet. I want to build the electronics myself in order to get a better understanding of the system , while making it easier to trouble shoot .1. I have owned a CNC machine for 12 years. I can't count the times I have had to hit the emergency stop. Anything from a software glitch to a power glitch.If your good with electronics you can take a cheap ESP32-cam board and watch whats happening on your cell phone. If your into programming you can do a remote stop.
2. Instead of a tool changer my first upgrade would be Clear Path Hybird steppers, their is a YouTube video that shows this system going the full 8' of a 4X8 machine and returning to within a couple of thousands or less measured with a dial indicator.
3. Good luck learning the nuances of the Avid/Router Parts machine. My friend and I have been working for over 3 years up grading his 4X8 Avid/Router Parts Machine with end stops, limit switches Clear Path Hybrid steppers etc.
4. Keep a good sense of humor CNC can try your good nature.