If you are using INS13 and (after GPS and mag go green) the FlightData artificial horizon display works correctly (it looks backwards, since it goes left when you tip right, but it is correct), but horizon goes crazy when you add power, then you either have a mag and wiring problem or you have bad vibrations. Props MUST be balanced for this to work.
You can check for excess vibration by looking at Scopes (Accel) as you run motor up. Gyros go crazy if they see too much vibration. I'm going to make a guess that 1g of noise is OK, but 10g's causes crazy gyros.
There is a version of Complementary that does allow GPS and mag for
navigation, but I'm fairly sure that no version of Complementary (Basic) uses GPS or mag for
stabilization.
INS13 uses GPS and mag for both
navigation and
stabilization, so for INS13 GPS jumps or crazy mag will cause flight problems even in Attitude (non-GPS) mode.
When I help, I make some assumptions about the configuration. I wouldn't have guessed that you disabled "Zero the integral when throttle is low". Generally speaking, it is best to avoid changing things or at least set them back to default when you are done testing.
Maybe you accidentally clicked this and didn't know it... With that, if you still can't get it working, you might save (file -> export) this config in case you want to go back to it, and start over with an Erase Settings on the Firmware page.
Arm, start motor, take off (from level ground). Do it fairly quickly (say 5 seconds) to avoid windup, but I don't think windup is your problem.
You could take off the landing gear and strap battery underneath so that the arms don't touch ground and it is sitting on center battery bulge. That way when the motors start spinning, it can stabilize before it has enough power to lift off. This will help the windup issue.
I will make a screen capture of my accel scope while flying to give you a reference.