I downloaded librepilot super moon eclipse and saw an error flashing stating that the gas and the fcb are not compatible and might not work. I hAve attached a photo of it below. Please help me. 
Thanks in advance.

I haven't tried the Librepilot GCS yet , but for any openpilot board to properly work , the GCS version and firmware version should match.

In openpilot GCS , you just have to click on update firmware and connect your Hardware to get the firmware upgraded to the matching version. I think same should work with Librepilot.

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As for CC3D , development is already stopped , so I think if you can get the last CC3D supporting openpilot GCS (15.02.xx) , that would be best option.

I have the setup file for the openpilot GCS , if anyone needs it just let me know.

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