SL8082T - Additional GPIO's Problem

Dear All
In SL8082T module, as per the PTS some of the additional GIOP pins(GPIO 20, GPIO_22 , ect) are available from version 7.53, but unfortunately after lading the 2.53 software, GPIO are not visible for command AT+WIOM=2 …it list GPIO’s up to 16.

PST: AirPrime_SL808xT_SL808xBT_SL808xBTA_Product_Technical_Specification_Customer_Design_Guideline_Rev5_1

attached PTS and Module firmware details!!

Pls. suggest what is the right method(h/w & S/w) to enable additional GPIO pins in SL8082T.

thanks & Regards

Download FW B7.53.0.A1.201407231334 first then try to download the required firmware.
I heard that B7.53.0.A1.201407231334 is a transition FW and has some GPIO configurations set…