Thanks for the reply.
Changing filename/extension isn't really a problem as I can use the resolve screen that comes up.
I have thought about using Videopad to produce the proxies. It would be easier if the export function had an option to export in the original aspect ratio but a different resolution. To be fair, the other program I am using doesn't have that option either, I have just got into the habit of using that, and it is quicker and easier just to do a quick convert.
Even though the proxy files are sometimes bigger on disk, I can confirm that the preview does seem to come up quicker than when using the originals. I just wondered if I ought to consider reducing the frame rate, data rate or other variables too. If you don't think it will make much difference I won't worry about it 🙂
Cheers
Phil.