There's no need anymore to specify entitlement settings when building your custom apps in App Builder. Unlike the previous version of DPS, in DPS 2015 the viewers will retrieve the direct entitlement configuration at runtime. This does, however, depend on your integrator ID being registered with us. Have you contacted customer support to get your entitlement server registered?
With regards to public/private, that isn't a concept in DPS 2015. Are you attempting to do restricted distribution (where a reader cannot see content unless they are signed in and have rights to it)? If so that feature isn't supported yet in DPS 2015.
I already have some applications in the app stores (IOS and Google) that's configured with my integrator ID. This applications it's running over DPS 2014 with no problem. My integrator ID is already registered with Adobe.
I´m using the same Integrator ID for DPS 2015.
The Integrator ID for DPS 2014 work's on DPS 2015? Or something have to be changed with Adobe?