Arduino won't work with my Osepp 101 Robotics Kit Basics (OSEPP UNO R3 PLUS)

Please excuse my ignorance, but I can't get the Arduino environment to work with my Osepp 101 Robotics Kit Basics (OSEPP - OSEPP™ Mega 2560 R3 Plus). I've tried to get Arduino 1.6.8 to work with the kit on a Mac (10.11.3) and on a Windows PC running Windows 7 Enterprise 64-bit. I can get the blink sketch to work, but that's it.

I'm 95% confident that the robot is wired correctly. I believe this likely to be a problem with drivers or COM ports, but I don't even know that for sure. Any help would be greatly appreciated.

Uh-huh:
I believe this likely to be a problem with drivers or COM ports

You are wrong since the you write that you were able to upload the Blink sketch and that it works.