Splitting Browser Windows for Portrait External Monitor?

Hi, I've got a portrait monitor, yay me.

I would like to initialize a work environment, with four Chrome windows.

I'd prefer to have them each at 25% of the portrait height.

I'm finding it very confusing going.

First of all, there doesn't seem to be a "bottom top" and "bottom bottom" setting by default in Keyboard Maestro. Same for "top top" and "top bottom".

I'm not sure how to solve this. i've got stuff like

SCREENVISIBLE(Second,Height)*0.25 which makes it into one of those 1/4 of portrait things, but not sure how to layer it since
SCREENVISIBLE(Second,Top)*0.25 just seems to post it "somewhere".

Any suggestions on how to do four 25% 25% 25% 25% Google Chrome windows so that they're not on top of each other?

So, here's where I'm at.

The first window will be Top-Top, at a specific URL:
image

This places it at the top of the Portrait monitor screen, at 25% of the height.

The second window will be Bottom-Top, at a specific URL:
image

So far, so good. Now, the tricky part is how to make sure the rest go to top-bottom and bottom-bottom.

I'm looking at
SCREENVISIBLE(Second,MidY,-50%)

but to no avail, it just places it at the top of the screen

But then when I try to go to this:
image
All I get is the window title shown right at the bottom. this is really confusing.

So, after tons of fiddling, I was able to conquer the "top-top" & "top-bottom" by using

SCREENVISIBLE(Second,Top)/0.046

Now, that does not feel very intuitive to me at all, and I'd love to know how this is properly done by experts that know what they're doing.

Unfortunately, trying to duplicate that behaviour for bottom-bottom, just places the window right at the bottom of the screen with only the title displaying:

what should i be doing to get this to work accurately? also, the top-bottom and bottom-top windows are just slightly on top of eachother, so 0.046 is not exactly lining up here. guess i gotta try 0.0465 or something like that :-o

edit it was 0.0462 that lined them up suitably okay for top-top top-bottom, but i'm still not sure how to get the lowermost one to line up properly.