Gecko ERR/RES Handling

I am having problems understanding just how to handle the Gecko ERR/RES
terminal.
I have one print that shows mechanical switching, another that shows an
electronic circuit to shut off all Gecko Drives when there is a fault. I
have another that shows a resistor being used. Just a little bit of
confusion here.

So please tell me how it is actually supposed to be handled.
What is the perfect highly recommended "last word" on how to do it?

Also where does the +5 for the Encoder come from, is it an external +5 volts
that is fed in on the +5 ENC terminal? If so where is the -5V GND reference
fed to, the
ENC- terminal?
I know that I can get the +5 from the game port, however in my case I have
+5 volts available, and want to know how both the +5 and the GND are handled.
Is there any connection between the ENC- GND, and the Power Gnd.

A clear concise, "last word" on the matter post would be helpful.

thanks,
bill