I tried to follow your steps and made a sample project (you can find it attached). On my side it works as expected - when double click on the ribbon tab the ribbon is not minimized, but I might be missing important part of your implementation. This is why I believe it will be better if you send us a sample project or if you can modify the project I sent. This will allow us to examine your implementation and try to reproduce the issue locally. We can then modify the solution to work per your requirements and send it back to you.
Also, can you confirm that you are using binaries from the last release (Q1 2015)?
Thank you in advance for your cooperation.
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