---> link to P3A amp 60-80W Power Amplifier

I am using Proteus ISIS on my college and i try to check all calculations with it.

THE BIGGEST problem is the calculation of Q5 base current, here is pic from Proteus:

i dont have a clue how to calculate it. I understand how to get Vbe multipliers current, but i dont understand how to get that Q9 emmiter current (or Q5 base current).

and one minor problem is in differential amp - in Q1 and Q2 base currents.

Q1 base current is smaller then Q2`s because base resistance of Q1 is bigger (24200 ohm, while Q2 resistance is 22k). This is all clear but i still dont have an idea to calculate it.

Thank you very much