Thanks for responding.

TD, I decided to start over with a new alpha plane exactly as per your suggestions and, after setting it up, I let the scene render overnight (I stopped it this morning before it completed). The result is as per the image.

A few comments:

1. As you can see, the rain drops are still much too large and extend beyond the apparent alpha plane (Actually they are identical in size and location as the third image in my original postings so I've replicated exactly what I did before!).

2. The edge of the alpha plane (apparently a cube - see below) can be seen by the artefacts across the sidewalk and road (the corner of the cube is seen clearest at the left hand steps).

3. Obviously, from this, the alpha material setup bears no relation to the alpha plane.
   Why is this? (I tried both automatic and flat vertical on the material as well as linking the plane to the camera with no difference)

Incidentally, I'm having difficulty in seeing the alpha plane in the orthoganal views - the only way it can be seen is by switching to wireframe box view which, bizarrely then shows the plane as a very large cube!

Fixer, I've searched through the object collections and can't find the cylinder anywhere. I tried what you're suggesting as per the Simulating Rain tutorial in the manual and got thoroughly confused as the manual wording is rather imprecise. Also, the tutorial makes reference to a Rain scene containing the cylinder but I can't find that either!

I've got the download version of Vue8 Esprit with latest updates.

I'm obviously missing something so any help will be much appreciated!