When you start the download, the Download Manager will display the Progress window. At first, the individual downloads are displayed as Preparing.
The Download Manager will 'prepare' a file by splitting it into multiple chunks to enable multiple downloads; and to create a large empty target file to receive these chunks. If you look in the file system, you will see the download files grow quickly but then during the actual download they appear to remain at constant size. This is because these large empty files are being 'filled in' with the downloaded data.
During the actual download process, the Progress window will indicate the progress and estimated time left:
Any errors will be indicated and displayed at the end of the downloads. With a lot of downloads, it is possible there might be an issue and you have to re-download the erroneous file.
After downloading, the Download Manager will un-compress the road pack files into the required data structure (see Overview of the Ultra System for details).
You can stop the download at any stage by pressing the Stop button.