I'm so sorry I missed this. I didn't have auto-notifications turned on for this forum and I didn't realize this was here....
To answer the question:
Unfortunately, the VE3D renderer doesn't provide a true, hardware-level vblank so you know when the screen is finished rendering. We know when the software side is done, but the actual render to the screen. That is why you're seeing the tearing.
I found this to be an issue on slower machines with older video cards, like my laptop with a GeForce 7400M chipset. On my desktop, a quad core with a GeForce 9600GT chipset, it's quite speedy and the tearing/flickering issue isn't present.
Unfortunately this is about as good as it gets..sorry!