1. Start the download of the ISO
2. When you have more than 500KB, go to "My Shared Folder" make a copy of the .DAT file
3. Change the extension of the copied .DAT to .RAR
4. Double click the RAR file to open it with WinRAR 3.11.
If the header of the RAR was downloaded, you will be able to see the content of the ISO. This tip also can work with ZIPs, RAR and SFX exes.
This is helpful to check if the ISO has the files you expect should be there, before the download complete (several hours later).