I did the DXB to DWC transfer today with mixed success.
When I checked in at Auckland, my luggage was tagged to my final destination. I didn't think anything of it at the time, but later wondered how that would work with the DXB-DWC transfer. When I arrived in DXB, I checked with the luggage office who assured me this was correct and they take care of the road transport of checked luggage between DXB and DWC. Great. I cleared immigration and followed the signs to the bus.
The bus runs every half hour and takes about 1.5 hours from T3. It would be a lot faster but it waits at T2 for about half an hour. If you wanted to save some time, you could consider getting a taxi to T2 to get the bus.
I didn't have high hopes for the bus, but it's actually very good - a high-end tour coach rather than a "bus".
Got to DWC and asked about luggage again at check in and was assured everything was under control and my bag tag was entered into the Flydubai system etc.
The airport is a much more pleasant place to be than T2 but doesn't have as many food options - just Costa, McDonalds, a Heineken bar, and a cafe/bar looking thing that I can't remember the name of. The Marhaba lounge is mediocre (but better than T2 from memory) and doesn't have showers. Unfortunately smart gate registration doesn't carry over from DXB and the immigration process was slow. Looks like it's all bus gates and about as inefficient as T2. We ended up standing on the bus for half an hour beside the plane.
Arrived at my destination but my bag was still in DXB.
If I had to do it again, I'd ask them to check my bag as far as DXB only, and transfer it myself. Or at least make sure you hand-carry a few spare pairs of socks and undies.
Such a pain they couldn't get it 100% right.