When you download multiple products at once, the products you purchased will come as a ZIP file which have to be "unzipped" or "extracted" to allow you to access the files it contains. Many of our bundle products will also come in a ZIP file for your convenience.
Most computers today come with a zip utility, you should be able to right click on the ZIP file and choose to "Extract all" and hit continue or enter and a new file will be created that you can open and access the files it contains. If yours doesn't have one we suggest 7zip which is a free download. You can find 7Zip here - http://www.7-zip.org/. Once you have a zip utility installed, just right click on the file and choose to "extract all" and a new file will be created which should contain the files.
If you continue to run into problems please let us know your order number and the titles of the products you are trying to download and we can look for a different solution.