Use the gold spring for testing purposes. It will allow you to keep the operating pressure as low as it can be. Install the largest carrier that doesn't produce a leak. Basically, you should keep increasing the carrier size, using the same white oring, until you develop a leak out the front. Then go back to the last smaller one that didn't leak. That will be your carrier and oring setup. Now its just a matter of increasing the velocity until the gun cycles. If the regulator piston assembly is bleeding too much air off, then you might never reach a high enough pressure to cycle. However, using the gold spring, it shouldn't be an issue unless the regulator piston assembly is really bad.
Check for bolt interference. The level 10 bolt is really sensitive to friction.
Check the body washer to make sure it isn't causing friction on the bolt. Over time, sometime the body washer can get squeezed inward. If this occurs, just run a round file through the center to clean our the burrs and open it back up to the original size.
Also, try cycling without the barrel. If the barrel isn't centered in the body properly, it could cause friction issues with the bolt.