Modify an open source chess program

I need some modifications to a chess program wrote in Java or C#. The programmer can choose the program. The only requirement is that the choosen program can read full pgn games, and accept FEN notation. The modification I need is quite simple. Probably some buttons in the principal screen. From a choosen position, the program will show a little board with a resume of the board position. For each square the program will count all pieces attacking it, and it will colored the square to represent the result: a white square means white > black, a black square means black > white, and maybe a blue square means black = white. Each square may contains the result number. For a given square, the program may keep this resume. So the user can choose other squares, and the program will show a comparison of each one with the very 1st. It can be some grafical window. I need a small function to generate all the moves from a given position, and they may be entered in the original PGN notation. I can give other details, if needed.