Thanks for the kind feedback!
The reason it's not yet 'One Click Plugin Updater' friendly is because of the packaging, which I'm aiming to change for the benefit of becoming compatible.
Although looking at the download stats of 'One Click Plugin Updater' it doesn't look like a lot of people are using it. Maybe it's my paranoid self about installing new software blindly, but I never liked the idea of one-click-upgrades.
But that of course won't stop me from repacking cforms, the only problem is the inflexibility of the WordPress.org plugin repository. You can't yourself determine the root dir of the package and it is now set to /cforms/. Even if I made it 'One Click Plugin Updater' compatible it wouldn't be a clean upgrade because it'd create another directory next to your existing /contactforms/ dir. (I hope I made sense...)
So while I'm waiting on WordPress.org's answer it'll have to remain incompatible.