|It seems to me that the fault is with the video capture program you are using. Everything you stated about their website seems quite normal.|
Tread a bit carefully about contacting ITV (as per #1). They are likely to regard downloading the program onto your HD as illegal, unless you are using a downloader that they provided for that purpose.
BBC do provide such a facility but the file cannot be transferred and only functions for a limited length of time - but I guess you know that.
Always pop back and let us know the outcome - thanks