Windows XP/Windows 7 Interprocess communication

Summary: 2 ABSOLUTELY independent applications need to communicate between each other. First application is given to us, we do not have any control over it, it has Forms that need to be filled out. The client need to implement the second application that will fill out these forms. This project is for proof of concept so the application would listen for keyboard input and fill out one field after "Enter" is pressed. We would need to do another project that would listen to input over http and fill out the form based on the message received but this project is for proof of concept only. Please read the project first and write the word "Understood". Also write your questions, steps and suggestions to complete the project with a short description of what you understood.