the download includes only one file, whats your problem?
why you do not upload all needed files in one zip

ARE YOU SURE YOU PUT THE RESTORE ON THE install THEN TRY TO LAUNCH THE
OSInstall.mpkg FROM THE os (your step 4)? Does not work and makes no sense.
Further what is the download file for.....as others have said it is B.S.
Also me thinkin, why can't we go to the folder and open the install itself?????????? I would like to do this because the spelling, caps etc is quite important and makes it hard to type to find it.....just go through the heirachy and find it and double click on it....golly it will launch, p.s. what is a "Splash" ??????
IT WOULD BE NICE IF PEOPLE DID NOT POST WHEN THEY CANNOT COMPLETE THEIR THOUGHTS....it only complicates things for us who are trying so hard to understand.