What are you not understanding? I presume you downloaded the product from the Android Market and it installed on your phone. Are you needing to know how to make it work with your PC, or did it somehow fail to download?
RDP requires a clear network path to your PC. That means you need to configure the software with the IP address of your PC, then you have to make sure the phone can connect to that IP address.
Configuration depends on where your phone is relative to your PC.
If your phone is on WIFI in the same network as your PC
Then all you should have to do is:
1) Configure Windows Firewall to allow port 3389 (default RDP port) or whatever port that product uses
2) Get your PC's IP address, and give it to the program on your phone.
2a) Hold the [Windows] key and press [R]
2b) Type "cmd" (without quotes) and press [Enter]
2c) Type "ipconfig" (without quotes) and press [Enter]
2d) Your IP address will be listed. It's probably 192.168.x.y, where x and y are some number
If your Phone is using 3G, or on a WIFI network other than the one your PC is on
In this case, you need to connect through the internet. This involves everything above, plus:
1) Look at the "ipconfig" data from the previous steps. Find the "Default Gateway" address
2) Enter that address into your browser on the PC
3) This will access the Router's configuration webpage
4) Make sure the firewall allows the proper port to enter
5) "Forward" the proper port to your PC's IP address
These are general steps. I'm not affiliated with that product, but I'm somewhat of an expert in that technology, so feel free to write back or PM me if you have more questions. All of this [often confusing] configuration was one of the reasons we wrote PhoneMyPC.
Configuring Windows is pretty simple, but configuring your router can be very different across brands; I can help you do that, later this evening. Let me know what OS you have and perhaps we'll toss our product on there so I can access your PC and help you with your router configuration.
Follow the instructions on that web page, but ignore the stuff about your phone; you don't own this product, but I do. I'll use it to remote-control your PC with my Droid.
When you configure the program, pick a user-name and password, then PM those to me.
I'll be available around 7pm PST, and I'll help you get your router set up then.
Bboy. Just purchase phonemypc and you'll be able to easily use your computer from your droid. Fyi softwareforme.com is the developer of phonemypc. You're not really going to have phonemypc's developer help you set up a competing software, are you?