I tried to do the nextgen enrolment, and they had only one machine that could read passports. However, that machine couldn't completely read my passport. The CLEAR representative scanned the photo page without problems, but then for the step of scanning the back page, which has a barcode, the screen only kept the spinning icon. Ultimately I wasn't able to convert to nextgen.

Does a global entry card work for nextgen? I see some of the posts above mention it. The representative said my passport card could not be used, only drivers license or passport book.