Hello JP,
Thanks for replying. I must have made a similar mistake. While on the Mac I checked I was opening 1.5.3 but was still getting the error. I installed a clean copy of 1.5.3 on my Linux machine and MonsterSketch compiled without any problems. I'll have to clean the Mac up and try to get it working properly. I have both IDEs there.
Thanks again for taking the time to check that. I have 95% of the Data Monster components here minus 2 servos. Looking forward to working with it.