[quote user="GEOFF JACKSON"]My first question is, does the active project in the Project Explorer window (or anywhere else for that matter) have to be specifically set up for debug ? At the moment it's set to "Active - Release" in the Project Explorer.[/quote]
You are referring to the build configuration for the project. The difference between two build configurations is the compiler options. I presume you are using a compiler of version 6.2.x. If so, then building with the debug options is not required. However, your level of optimization could make a difference.
Try lowering your optimization level and see if that helps. You can either change the level in the current build configuration, or change to the debug build configuration.
More information about this tradeoff between debug and optimization is in this wiki article.
Thanks and regards,
-George