I was really grateful that you fulfilled my request for a files.mail.ru plugin, but it seems to be having teething troubles. Some links work beautifully, but more than half (e.g. this one: [files.mail.ru]) fail with 'Error: File name not found'. The link is definitely live. I notice that the ones that fail seem to have several files referred to by the one link: could this be the problem?

Thanks for your help

sample link

You were 100% correct.
I did not find any links with several files listed when creating the plugin (v1.0.0)
Those links are now supported in plugin v1.0.1