NOTE: The following applies only to QuickTime 7.3 under Tiger.
It's been something of a challenge tracking the rapid deployment of all the QuickTime revisions, ahem, to say the least. While our Apps are working great under both QuickTime 7.2 and 7.3 (and probably 6.5, although we don't test it), they have made some changes to QT Player Pro that will require an update to all our little virtual cam apps for recording. We definitely want to do this, as the camera output from DotMatrix and Qamera is ARGB with an alpha channel which is something that many VJ's and PRO video nerds will love. If that sounds like you, either use an alternative movie recording App, or downgrade to QuickTime 7.2 -- QT 7.2, which we used primarily during the development of our new ARGB camera technology, works great with both Qamera and DotMatrix - you can record a Device Native 640x480 with an alpha channel and bring it into Final Cut. Etc. Or pipe DotMatrix into Quartz Composer and have the video texture alpha ready (at least, that's the theory).
BTW, we did release a CamCamX upgrade today that fixed a problem preventing MACAM and other third party webcams, including Qamera from working correctly. Now, on Tiger, you have a choice of either starting CamCamX first, then Qamera, or vice versa. On Leopard, with our X5 driver installed ("Leopard-Only.pkg"), it doesn't make a difference.
If you have any questions about routing video signals, please send them our way.