Ok I'm back with some good news and some possible bad.
First the good!
At this moment I DO have Riven running in my Win7 64bit system!
Now for the possible bad....the best solution for people who have the 5 Disk version of the game is you will need to install the game in another version of Windows.
I did it using my Virtual Box and my copy of Windows XP that I installed to it awhile ago. Once the game was installed, I then had to patch the game. (This is the usual game patch). Then I just copied the whole Riven folder to my Program Files (x86) folder.
Once that is done, you need to grab a copy of the Unofficial Riven Vista Patch. It's a .zip file that you need to extract, then copy all the files in the Patch folder to your main Riven folder, then run the Patcher itself. It will need you to navigate to and select the Riven.exe which it should patch properly.
Next, in the Riven folder locate the Mohawk.w32 file and open it in a Text Editor. Locate the line: fEnableAudioProxy=true and change it to false
Last step is to right-click this new Riven.exe and edit the Compatibility and select Windows 98/ME Compatibility. Tick the Disable Visual Themes, Disable Desktop Composition, Disable Display Scaling on High DPI settings and finally tick the Run as Administrator