I have no idea how a monoblock LNB works, so keep in mind that what I tell you may be wrong...
I think you have to change the configuration of your satellite from 'Universal LNB only' to enable the switching between the 2 networks (depending on the number of connections on your diseqc switch)
[= your adapter.png screenshot]
I also have a DVSky S960 and i have connected it to a diseqc switch with 4 ports. 3 of them are used to connect to an LNB. These are just single LNBs, pointing to Astra 1, Astra 2 and Astra 3 respectively.
So, in the satellite config I have selected "4-Port switch (universal LNB)".
[see adapter_gert.png]
Once you do that, you can assign the different networks to the positions on the diseqc switch
[see adapter2_gert.png]
I have added the diseqc and lnb position to the network names - just to make it easier for myself.
[see networks_gert.png]