I had the same issue and putting backticks around the column names “key” and “type” appears to have allowed me to create the table and my errors stopped.
David, your advise solved my issue. Thank you very much!
If I may suggest that you put those examples in your documentation or clarify that Author section, as it was a bit unclear to me. However, I will go to the WP_Query documentation if I run into future MLA issues. Thanks again from a novice WordPress developer for the great plugin and support!
