edit: OK, figured out the problem. The 18.10 driver has only been released in Europe and ImagePrint is only compatible with the US drivers (I blame the metric system). So if you're googling around for the latest Canon drivers and are using ImagePrint be sure you stick to the Canon US site.
I upgraded my Canon PRO-4000 driver to version 18.10 released earlier in October and started having layout issues when printing to cut sheets with ImagePrint. Image was shifted down 1.5" and right 0.5". Downgrading to driver 16.10.1.0 fixed the issue. Just wanted to give anyone interested a heads up to save them banging their head against the wall.