When the side bar (navigation, search/found, etc.) is not open, the macro works as expected. When the side bar is open, then it does not work as expected.
What happens if you zoom the Word document to full size first? (Not so-called “Full Screen” but fully zoomed out.)
On my macOS 10.12.6 Sierra system with Word 16.16.10 from Office 2016 I see weird problems when resizing a document with Keyboard Maestro, AppleScript, and Moom.
Microsoft is doing something peculiar to limit how the window resizes.
Try running your original macro several times. On my system it will eventually be fully repositioned and resized, but it takes 3-5 runs of the macro to get there.
I did not know Spectacle before. I did a search and found out it's been discontinued.
Before I bought KM, I used to use BetterSnapTool. It's made by the same developer and is free. After I bought KM, I switched to KM because I like the KM editor better. It's more simplistic to me and it's easier to locate macros and edit them.
Now due to the Word problem, I think I'll use BTT for that purpose.
I use Word 16.47. It's constantly updated.
What's up with the developers? They don't have any worthwhile information about the app or screenshots of it on that page. To me that says they're not serious at all about getting users.
That said – upon @hello's recommendation I downloaded and looked at it. It's very good for a freebie.
But the devs need to wake up and smell the coffee...
I think BST is no longer free, but it's inexpensive ($2.99).
For the difference in features and price I'd buy BTT at ($8.50). I see it still works with Sierra, so I'll give it a spin. Been a while since I looked it over.
Keyboard Maestro resizes the window, and the panel part that shows the document is controlled by Word. I can't really see what is wrong in your images. The document pane is a scrollable area, and if the window is resized, the document pane may need scrolling. Although I don't know what is happening with the tools at the bottom right off the window, as they should follow the bottom right corner of the window regardless of any scrolling of the document pane.