A colleague asked for help. She had installed Keyman 14 on her Mac (MacOS 12.01) but was not able to select it to use a keyboard. When I got on her computer, I found Keyman mentioned in the permissions settings, but it was not listed as an input source. I was able to add it by clicking the + then finding it in the list under Multiple languages.
On my own Mac, I had not yet upgraded to Monterey so I removed Keyman, then upgraded to see if I could then install Keyman and reproduce the incomplete install. When I installed Keyman, it asked if I wanted to add it as an input source, and did so without a problem. Maybe the colleague had not given this permission when she installed it the first time?
I guess the conclusion is Keyman 14 works fine with MacOS 12.01, but missteps in the installation are possible.
I sent her that page, she said it didn’t solve her problem. (And I can see if Keyman was not listed as an input source, it would not work).
Interestingly, on my Mac, Keyman is not entered in the “input monitoring” list, but it still works. So maybe that one is no longer needed for Monterey? It is listed in the other two on my Mac, accessibility and Files and Folders (for Documents).