To answer a question from Neil, I've created a small sample application of how I do spell check using word.
Anyone can download it from my Google Drive using this link:
PB 12.6 build 4081, windows 10, word 2010 and 2016 have been tested.
No database connection is needed.
It has a datawindow and also a richtextEdit control. You can activate the spell check by typing something and pressing the F12 key or by using the command button.
If the text doesn't contain anything doubtful, the spell check doesn't show. After checking the text, you have to change some text for it to work again on the same field.
There's still a flickering of the window caused by the activate and setting (in)visible from the code. I still have to work on that. (on PB 2017 that doesn't seem to happen).