Developing Composite node chapter for book 'Blender Basics' and creating examples for potential exercises I found that on latest CVS build 20/12/06 and previous CVS that Vector Blur gives the following error when rendering:-

tsk tsk! PASS_VECTOR_MAX left in buffer...

I have tried all settings to see if it may be a particular setting with no success. It can make Blender crash unexpectedly if you fiddle with the nodes too much.

I'm on a WINXP, AMD64 4200+ processor PC, with 1Gb Ram. NVIDIA GeForce 7600GT graphics card.

The attached file should have the textures attached to enable the composite. Just to explain the 2 pre-rendered images, one a background image, the other an alpha mask are composited with a vector blurred dial. This is to demonstrate how pre-rendering and compositing can save time with animation rendering. Here a 10 second sequence can be rendered at 800x600 in just a few minutes. Previous examples show how to create the steam-gauge itself using render passes to give complete control over its appearance, as well as how to pull a matte using ID Mask.

Colin