@Shii
I want to thank you again for your great guide/help and everything between! - cheers!

It finally worked for me, after reinstalling everything and reseting my tv.
Now i wont to share another experience:
As Shii already explaines in his guide, everyone who is using sound over hdmi has to give it up - but that`s not completely true
I`ll give you a short heads up about my setup:
LG 55lw4500 TV
NVIDIA GTX 580 (2x DVI, 1x HDMI, 1x DisplayPort)
Onkyo TX-SR608 AV Receiver
When i was really happy having a perfect Interleaved 1080p picture (Skyrim 1080p 3D at 60hz on a 55 inch tv

)
i couldn`t take the fact that i have to give up the perfect LPCM 5.1/7.1 sound in games and movies. (optical/analog is always lossy)
So I have made the following setup and it works perfectly!
What do you need? - 1x DVI to HDMI adapter oder DisplayPort to HDMI adapter
1. plug in the DVI/HDMI or DP/HDMI Adapter
2. connect your PC direclty to your TV with your adapter and a hdmi cable
3. grab another hdmi cable and connect your pc with your av receiver
4. if you turn everything on...nvidia will recognize two displays
(the av receiver is shown as a display and your tv of course)
5. reinstall Shii`s Acer/LG edid - over the correct display (your TV)
(the av receiver driver/display stays untouched)
6. Reboot
7. Nvidia will now clone these two displays
(cloning can produce some picture failures or delay`s)
8. instead of cloning - enhance your picture (nvidia settings) and set the TV as primary display
9. go to digital audio (nvidia settings) and set at hdmi your av receiver
10. check if your tv is recognized as DVI monitor (nvidia settings)
Now you will have your desktop displaying on your tv and the enhanced desktop (without) icons at your av receiver (if you switch to that output)
And thats it! - A perfect 3D interleaved picture and the full LPCM sound over hdmi with your av receiver!
kind regards!