Rough running @cruise setting

Thanks. The gaps are 0.6 mm.
The inclination of the blades are all exactly the same. 

"The settings are:
T.O. 5800 rpm
Climb 5500 rpm
Cruise 4800 rpm

Cruise is too low - Min 5000 rpm - better 5200 rpm. Yes I know 4800 rpm is allowed but you are a long way below Max Torque - even a slight climb will labour the engine. 

Try switching to Manual mode and increasing the rpm to 5200 RPM @  about 26.5 Hg - see how that sounds/feels.

"I had the prop balance checked and it was within the limit. As far as I remember it was 0.1 when 0.2 was the limit".

Dont know what you mean . To balance my propeller I did the following:

A vacuum balance on my carburettors.

Checked for prop pitch variation using a digital protractor and a Warp Drive bubble type protractor.

Checked for acceptable tip tracking (within 5mm)

Followed by dynamic balance in my normal cruising rpm range - several repetitions

I achieved a balance of 0.05 inches per second (ips) which I considered acceptable.😈