Hi, Mathieu.

When using the trial version of Neo HD, I encoded to full res, 1920 x 1080p intermediates.

The "light" version of Cineform that comes with Vegas doesn't support encoding to resolutions above HDV (1440 x 1080, 1.3333 anamorphic pixels). I didn't try encoding to that max resolution and instead opted for square pixels at 1280 x 720, but I presume the 1440 x 1080 anamorphic works and that you could retain the full vertical resolution that way.