I wasn't able to locate this particular subject on the forum.
You cannot feed single sheets from the top tray and print the exact image size to scale and centered on the sheet. Canon states the feed path for the cassette, the roll and the single sheet is exactly the same. Example: An image 15” W x 20” L will print centered and to exact size on a 17 x 22 sheet via the cassette and on a roll feeding from the top tray area. It will not print to exact size nor will it be centered when feeding a 17 x 22 single sheet from the top tray area. This appears to be a software issue to me. While on the software subject, it would be nice to control the printer via software alone vs. setting up the software and then making sure you push the correct buttons on the printer for paper type, feed location, etc. It is as though Canon wants you to use a roll only. No cassette and no single sheets.
Should you wish to print on canvas type media that must per Canon feed from the top, Canon’s advice is to purchase a roll but not single sheets. Any suggestion other than those offered by Canon?