Hi,
We can used lyx.org program to edit and design our Exam or quiz by this steps.
1- open AMC progam then --> new --> templates then select ( sample or group ).
2- generate pdf file in the 3 step as any amc project.
3- closed AMC progam.
6- open lyx program --> file --> new document.
7- file --> impoert --> sample tex --> select tex file from the AMC project folder.
8- design your exam as you like. Then ..
9- file --> export --> sample tex --> replace the orginal tex file in AMC project.

You can add text, table, image, but flout image or flout table not work.

Regards