The more recent MacBook 15" Retina models have a built in feature to detect graphics intensive programs and switch to the discrete GPU. The problem for SimuLearn apps is that the current driver set for the NVidia GeForce 650 card are not yet ready for all 3D applications. However, the HD 4000 integrated solution on the your machine is perfectly capable of running SimuLearn apps.

Here's what you need to do.

Download and install this program:

Once installed you should see a menu icon that allows you to switch manually between Integrated and Discrete video solutions. You need to select the Integrated solution.

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