[s2byus]

Although only one output of the switch is used, the receiver should command the switch to select the apropriate LNB/Satellite. Therefore, the settings of the DPP44 switch should be the same as if you had a diseqc switch.
The receiver Diseqc Port number settings should mach the input connections for each LNB/Satellite like:
Diseqc Port 1 if the LNB for 110 is connected to DPP44 input port 1, and so on for all 3 LNBs, depending on which DPP44 input port they are connected to.

Note that the DPP44 is actually a type of multiswitch that enables connecting up to 4 receivers, however, each receiver controls the satellite selection exactly like having a single 4x1 diseqc switch conneted to it.