Router Board 433AH-small Help Plz

Alsalam Alukcom =Hello ....
in First my english languge it's No good enough ... i hope you can understand me ..

ihave tow Mikrotik OS : the first one Working As PPPoE Server working verey good .
But the secend is router Board 433AH it's working as ap bridge with "XR2 600 MW" mini pci card , connected to umni antina "12dbi".
the Problem is in board configuration i try many settings but when i have 18-20 Online clients.(see pic 1A)
no more clients can enter to my network or to my PPPoE Server .in same time or synchronize the Coverage good it's between 28-44 dbm in distance 150-500M , and have many clients online to my borad-(see pic 2)

i have many Wireless ISP's they have many Channels in our Speace.
i need to config my board in Exception mode to be can work good,
i can open any disktop remote to enter my pc .
you can see my board configed .

Note: you can download attached file to see all pic too

the PIC's
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1A -

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board-pic.rar (626 KB)