Battery charger with LCD schematic questions

[NigthMoth]

Dear all

I was trying to hack/canibalize LCD display from an old battery charger, but I became more interested in the battery charger schematic itself.
PCB marked as GIANTOX ABS-300-03 20090427, so it should be old 2009 year design.

There is schematic i was able to transcribe (name of some parts was not readable and I was not careful enough and
physically damaged transformer T1 during its disassembling, but I belive schematic should be correct)

I found here explanation of "Primary coil side" working cycle, but I have a problem to understand "Secondary coil side" of this circuit.
My questions:

1)
I would appreciate if somebody can explain Q5, Q6, Q7, Q8 circuity, or provide a link with explanation of similar circuit, or at least tell name of this type of transistor network.
As I understand it is battery charging control circuit, but I can't get how it works.
My "reverse" analysis attempt:
"The battery is charging" symbl on LCD ->
V(P2) > V(P1) ->
Q10 is "OFF" ->
Q9 is "OFF" ->
U4 is "OFF" (U4 vref<2.5V -> V(NodeA, P1) < 4.34V) ->
***I'm stuck here***
battery is installed AND (Q5 and Q6 is "ON") ?
or
battery is not installed AND [(Q7 and Q6 is "ON") OR (Q5 and Q8 is "ON")] ?

2)
What is the purpose of Q3 and Q4?

3)
Is R6 a "bleeder resistor"?

4)
What is the purpose of 2 Ohm RF resistor?

 

[std_match]

1) Q5, Q6. Q7, Q8 seems to be an automatic polarity switch, so the battery can be connected either way.