Finally got a response from WRMK regarding the issue of A2 cards still being incorrect. This is their response:
"Hello. Thank you for contacting us! The sizing is correct on the A2. The tool only works on the ½” increments. The envelope size is the closest the tool makes for an A2 card. Please let us know if you have additional questions. Have a great day!"
So...the 4-1/2 x 5-1/2 stays. We just need to work around it if it bugs us or, leave it the way it is.