Thanks Again !!
"No printer was found on any option" referred to the add dialogue ONLY which has 5 or 6 tick boxes included - all of which I tried with nothing found.
"OK I have zero experience of setting up a switch network."
All networks depend upon what switches actually do - though many folks mistakenly refer to them as 'hubs', which most are not anymore due to the hubs' limited natures.
"so do we have 3 PCs with cables (ethernet?) to this switch box?"
It is just a very typical small office wired network - nothing odd about it.
All local, yes:
"...normal cups expects to find a discovered printer via the router or via its local area network "
All have typical 192... IP addresses.
Nothing I am asking about regards internet printing of any sort !!
The several users all send very certain print jobs to the Canon printer, and that is all that this is about; the 2 remaining win-doze users do so 100% trouble free - they will not be win-doze users if/when it can be shown that Linux is the better choice for moving forward.
NOT being able to detect & install this LAN connected printer to the Linux OS is pretty much the rock in the shoe of this whole thing !!! (For me, especially.)
The hangup when I went through this page's directions before was...:
My own bafflement at giving it the local IP & having it either gripe about the syntax, or finding nothing there ??
Different places seem to require differing (yet EXACT) ways of entering responses as is the Linux way - and admittedly I do not always get the EXACT syntax PERFECTLY right in working at this stuff.
VS. doing all this under win-doze:
The printer is seen easily AND the driver just installs almost instantly is VERY different than pushing through this FAR too-lengthy process wherein the printer is NOT seen easily and if/when it may be seen at all - the driver installation (thus far...) has been like trying to hammer a BIG square peg into the smaller round slot !!!
For crying out loud - it is just a common thing - a printer shared on a tiny LAN for several users - and not even an off-brand or strange printer at that - but after what - 2 weeks of beating on this for (what should be...) a 10 minute solution - I have a friend who already thinks this is for the birds - and I am getting close to agreeing with him on this ONE aspect of it !!!!!!!!!!!!!!!!!!!!!
This is NOT turning out to be a VALID method of showing ANYONE that Linux is a better choice - despite what I personally know of it via my very lengthy experiences - as it is all new to this user which I am trying to help to see just how much better it can be.