Well, after a short collaboration with my team's lead programmer, we agree that for the robot, 255 exceeds the max value of what the robot controller can understand. 254 is the max value, I believe. Try changing it to that and then running the program. That should help
EDIT: Another idea is to check your var declarations, and make sure you have everything declared, as well as checking constants and SERIN and SEROUT. Also, try unplugging the serial cable from the program port and resetting the bot. When we had basic run errors and did that, they usually went away. Otherwise, we turned to the lead programmer and made him go fix the code
