I'm not familiar with Cubase AL6, but the CMC comes with AI6, so it should work with that. There is an update 6.0.7 to AI6, not sure if this affects the CMC. On the other hand you might try downloading the trial version of 7.
Further than that I suggest, if the problem continues, that you use an easily reproducible example and describe step by step, the procedure you're trying to follow.
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