I know what you mean as the many times I tried to WILD I ended up drifting into my thoughts, which I was sleeping, but thinking at the same time & awoke to it being like 4 or 5 hours later to find that nothing happened but I was still thinking about trying to WILD drifting in & out of consciousness. It was like watching a blank screen for what seemed like about 30 minutes.
Anyway about the dream clock, I don't think it matters but I'm not completely sure. I tried it once in a DILD, on a piece of paper .. taped to a computer screen ..
Click here to see the hidden message (It might contain spoilers)
I put in 5 hours for Real Time & I think about a day or 2 for the Dream Time. It was a school day so of course I had to woke up later .. but it did work & the rest of the dream was fully lucid & adventure filled (people turning into blank "paper men", me having to fly away only to fall in a mysterious village where people dressed in Spartan clothing told me they had to fight off big cats that were terrorizing their village, but when I flew into the cat's village & kicked one in the face, they looked helpless, defenseless, in a "wtf dude?" sort of expression. Needless to say, the dream ended with me destroying the village of the Spartans forcing them to apologize & live with the big cats, this was separated in about 3 diff. dreams & it felt like a day.