If you go to Articles at top of page, then 3gx how to. Tony has the software versions for the 3gx. I have found version 2.1 to be the most reliable. Hope this is what you require.
What issues are you having when you try to install it? Giving us a place to start will help out a lot. I have installed the 3GX software on my W7 machine a few times and got it working.