Hello,
Sorry to hear you are having trouble.
I have an issue with my setup.
From the looks of it, you have had MP for a long time - I suspect it has been working fine until now. What changed?
Nothing on that page applies to this issue I'm having.
In the Seamless grid, if I right click on Laptop 2 and go into "Alignment settings...", then check the box to "Align bottom edges", then my mouse *DOES* maintain its vertical position when moving from Laptop 1 to Laptop 2.
So the documentation did help then, that is good to hear:
https://support.stardock.com/space/SHC/1381597224/Seemless+Connection+Settings#Alignment Settings
Its very difficult to visualize complex arrangments when there are multiple PCs involved all at (no doubt) varied resolutions and scaling. We then dont know how the MP grid is laid out or the mouse path the user is employing and what is expected by following it.
Then there on the terms used, I dont know what this means:
but warps down the bottom going back the other way.
Please post an image of your MP Grid like so:

Then post a drawn image of what the actual PC configuration is. Example:

You can use a design app of your choice of use this link to request access to the one I have done there:
https://stardock.atlassian.net/wiki/spaces/~5e2606abc9ecb50e76b89d76/pages/edit-v2/1522171907?draftShareId=a827ffe4-7ee6-4076-bf11-9527d55b0677&inEditorTemplatesPanel=auto_closed
Also, a video (with your phone would be fine) of what is happening and commentary of what is wrong vs expected.
Sean Drohan
Stardock Product Lifecycle Manager