FYI for anyone reading this wondering if SDM does in fact allow the SD630 to be used with a USB remote I can confirm that indeed it does work. As for synching two SD630's I don't know but if all you're looking for is a way to use a cable remote with an SD630 this will work for you. In fact it should work right off the bat without having to load a remote script or enable remote like in "regular" CHDK. Note you may have to check "disable USB download" by going into the menu>advanced menu>serial comms> and then checking the disable USB download option. This prevents the camera from thinking it's being connected to a PC and going into "download mode".
Just thought I'd add this info for anyone like me who wasn't sure what the final answer was regarding an SD630 and a usb remote.
