2. After going through the install wizard this window will appear. Click "Install DreamScene". If a window doesn't show up you can search for "DreamScene" on your computer or locate the install folder in "Program Files" and click on "dreamsceneseven.exe".
3. You can now use any .wmv file as an animated background! To use a login screen as your background choose one from the list above or go here to see a list of all available animations. An imgur gallery of all the animations is also available here.
4. After downloading the .wmv, locate the file and right click on it, then click "Set as Desktop Background".
5. Your animated background should now work!
An alternative program called "DreamScene Video Wallpaper" is also available as an alternative to the standard DreamScene mentioned above. You can download it here. The advantage to using this program instead of the official DreamScene is that it allows you to play multiple animations in a random order as well as change other playback settings. This program is also compatible with Windows 8 while the official DreamScene does not appear to be. Please note that this is a third party program and is not official.
I've tried to include every login animation I could find and uploaded them to that collection. If I've missed any of them feel free to tell me or send me the .swf or .wmv of ones I missed.
All these animations were created by Riot Games and some custom ones were made by Dyloslawer here.
Note: Windows 8 users must use the alterative program called DreamScene Video Wallpaper. Standard Dreamscene 7 is not compatible as far as I know.
Note: All backgrounds will be 1280 x 800 resolution (with the exception of Classic, Halloween 2010 and Trundle) because that is what the League of Legends client uses. There is no way for me to change this, it's completely up to Riot.
Note: If the background ever stops animating right click on your desktop and click "Play DreamScene"