setting up a 7 ch airplane with dual aileron,flap

Hi, I'm becoming crazy trying to set up my bixler 2 with my Devo 10 with deViation 3.0 and RX1002 10ch from walkera.

I need 7 channel because i have two aileron and two flap.

I don't even know how to abilitate the aileron stick to move two aileron at the same time.

Can someone explain me how work the deViation software? Maybe starting from the instruction for dual aileron. Thanks!