Many thanks, I'll take a look.
Andrew
Having now gone through this process, I thought someone might benefit from my experience: it turned out I had version 13.0l which came with a white yetti box, white yetti start-up screen and an Oz CD-ROM, the latter I didn't realise I had until I downloaded the yetti version of V13.0t from the above link and it didn't like my disc; it turns out I had an Oz CD that I hadn't looked at since the original install and I just assumed it was a yetti, same as software start-up and box.
Anyway, once I'd downloaded the Oz version and installed it, I now seem to have V14.0c with the Oz start-up screen. Can't say I understand why the process seems so complex, nor why I now have V14.0c when I thought I was installing V13.0t, but at least it works now and may be this information will help someone.
I should also add that there is some discussion on the AM13.0 forum about problems with the registry and installing different versions, but I didn't need to resort to this.
Best wishes,
Andrew