some quirks of my KVM setup and Apple keyboard layout

Currently using this product, 

HDMI KVM Switch 4 Port - 

there were some quirks which I had to work around. 

1. The Dell desktop running Linux Mint needed the USB keyboard to be mapped to it while booting, or else it would boot into Windows instead, even though the default boot sequence was set to Linux. Probably because the "fail-safe" boot option is different, when it beeps to indicate "No keyboard detected."
2. The KVM switch defaults to number 4 on power up, not number 1. So, the Dell desktop needs to be connected to 4 and not 1, for booting up without having to hit the KVM switch.
3. The Mac mini can boot OK without having the KVM mapped to it, but if we leave it on and not logged in, the login screen blanks and we can't get the screen to come back to life with the keyboard or mouse - we need to short-press the power button.
4. The Mac mini default keyboard mapping was showing the Indian rupee symbol ₹ instead of the backtick symbol ` for the key to the left of 1 (perhaps after the upgrade to MacOS Tahoe). Since I need ` for markdown on github etc, changed the keyboard layout to "US" from "ABC India" which was the default. For this, following this,
   chose Apple menu > System Settings, then searched for Keyboard in the sidebar. There, Input sources > Edit button, the small + button at the bottom left to add Input sources. Quite easy to miss.