Because of that it would be very nice, if someone can upload the Mod as the simple exe-file.

Downloading with Gamefloodclient first seemed to work, but after finishing the download i couldn't find the exe-file anywhere on my computer. Installing via Gamefloodclient returns an error and downloading it again also doesn't work, since the client states, that it was already downloaded.

Having problems myself: see my thread http://forums.civfanatics.com/showthread.php?t=254921

Alternatively, log in to GameFlood.com and find the mod. There should be a link to a chap called Nathan (GF_Nate) who handles things their end. You can PM him for help. I can't guarantee it'll work, but he will try to help you.

Downloading with Gamefloodclient first seemed to work, but after finishing the download i couldn't find the exe-file anywhere on my computer.

What browser are you using?
Maybe you should check the browser's settings? If I remember correctly, Firefox puts downloaded files onto your desktop by default. Not sure where IE pust them... ("/my documents" ?)

Try some of the troubleshooting from this thread:

http://forums.civfanatics.com/showthread.php?t=246589

...and then post in it if none of that works.

Specifically, check out this post first:

http://forums.civfanatics.com/showpost.php?p=6258824&postcount=32

Let me know what happens!