Are your downloads stopping mid-way with no messages or response? This may be a stretch, and just a thought, but are you using a linksys wireless router perhaps? I was having major problems downloading large files, and I found out that many people with this router were also having problems. It was addressed in a new flash for the firmware. Specifically the BEFW11 router but others may have the same problem, go
here and select your product (watch the version #) and operating system, and it will give you the latest firmware.
Or a quick fix would be to disconnect your router temporarily and use a direct connection to your high speed modem to download the file. If it works, then you might consider updating your firmware.
If you're not using a linksys wireless router, disregard this post...
Flip
EDIT: Sorry, just looked and realized you are in UK, so use the
UK page then click on your product and then click on firmware. You can use the US versions of firmware, but you may lose the higher channels (12, 13) on the router.