| Cheers Mr S, followed your links and worked it out. Blimey though, what a faff. Download Virtual Dub, Download a thing called Vobsub which contains a TextSub filter for Virtual sub, load all that, then export the translated subtitles from Subtitle Workshop into Sub Station Alpha format and then work out how to use Virtual Dub to create another AVI output file.
But, we've previewed the output and it's now creating the output file at 2 frames per second, so it's got a long way to go. Once that's cooked, all we've got to do then is find an AVI editor to trim the length of the original AVI file from around 40 minutes to the required 20 minutes of translated stuff.
Thanks for you help | 
Jools
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