@ronald First off, kudos for continuing to ask questions. I’ve found very few people who are as willing to say “I don’t get it yet” as you are - most people just give up. And that’s a shame, because there’s so much you can learn if you’re persistent. And you are, so keep it up!
As for the XPath action, two things. First, “XPath” is the name of a way to reference parts of a web page and XML (it’s more than that, but that’s enough for now). So it’s a generic term, not specific to KM.
Secondly, the action that was mentioned by @JMichaelTX was actually written by a member of this forum, and he says it’s broken. So we can’t use that.
As for finding the screen coordinates: In the Keyboard Maestro editor, there’s a menu item: Window -> Mouse display. You can use that to determine screen coordinates.
Just remember that in KM, when you refer to a screen area, it wants X,Y,W,H, which means Left, Top, Width, Height. So that means if you have the top left at 100,200 and the bottom right at 400,900, with width is 300 (400-100) and height is 700 (900-200). Assuming I didn’t transpose anything, which I did until I proof-read what I typed. 
Oh - one other thing about finding images in areas. For some reason, I’ve had to specify an area larger than the target image, or KM won’t find it. Not sure why. I need to ask Peter about that. Anyway, if you decide to use areas, play around with the sizes.
