Now TV is not mentioned in the Humax advertising for the 1100S, so one would guess not:
According to an existing post, Now TV is not supported (unless the service has been added since, but that involves commercial agreements between Humax and Now TV so it seems unlikely). However, there are other on-demand services that are supported, so you might be OK with them
If you are particularly keen on Now TV, you need to concentrate on smart TVs/players/PVRs that definitely advertise Now TV compatibility. If it's advertised by the manufacturer (eg on the outside of the retail packaging), they have a contractural commitment to supply - but if not, they don't and any support is entirely at their discretion. Otherwise it's straightforward enough to use a Now TV stick in one of the TV's HDMI ports and a sat receiver / PVR / whatever in another.