Well, i can only guess, that it is the following problem:
Rapidshare gives you a certain capacity of MB to download within on hour (a limit). If you exceeded this capacity you have to wait an hour bevor you can download again.
Mostly this capacity is achieved by downloading ONE video.
If so you'll get this message:
Du (84.191.196.89) hast in einer Stunde 49366 KB angefordert. (You (84.191.196.89) requested 49366 KB within one hour)
-> which means too much to download another video this hour.
I think that's the problem and if so i'm sorry i can't do anything against it.
But you can take a look after a video which is stored on www.megaupload.com (move your cursor over a link and you'll see the directory on the left bottom of your monitor), cause they have no download-limit.
I hope i could help you !
Greetings
Yvonne