I am almost sure that you can do what you want with easy C. However, I am having some trouble following what you want to do exactly and figuring out your problem. If you wish to drive your holomic robot, do not use both the RC driving blocks (i.e. two-motor or four-motor drive) and the motor module blocks. Simply use the motor blocks with the output being a variable. For example;
Retrieve a value from the joysticks using the Rx input block and set it to a variable.
Modify the variable however you like
Set the variable to a motor module with the output being that variable. Your robot will now drive based on how you modify the values being retrieved from the joysticks. For a program like this, there is no difference between easyC v1 or v2.
Hope this helps. If you still can't get it to work don't be afraid to come around these parts again
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