Hi. Sorry, but i wont be of much help to you, but understand what you are going through
We also have a 'non-sleeper', tried pretty much everything too, although havent tried cc. She is 3, 4 in August.
We had a while there where she was sleeping a decent amount each night and we were feeling human again but all that changed when she started Kinder this year.
She is back to waking usually twice a night, sometimes less or more.
Every night she tells me she will get a good nights sleep and see me in the morning light, but she wakes up, usually 5 or so hours later. Last night she woke before i'd had a chance to get to bed myself. She ended up in our bed at 2am and my DH went into hers with a sleeping bag, and she still had trouble getting to sleep even though she was in with me.
I have been to the MCHN and to the Dr very recently and niether of them was much help. The MCHN was no help-she's lovely and very supportive but she said her son was the same as my DD, always on the go and soaking everything up but hard to wind down and stay asleep. (my DD will go to sleep easily most nights). She basically said just to ride it out or do 'whatever works' for us to all get some sleep.
My Dr suggested putting another bed/matress in her room so that when DD wakes i coud try and resettle her, if that's what we want to do, and if she wakes again for me to put her back to bed then i would sleep in the spare bed in her room. That way it would reinforce her sleeping in her own bed. She also said "she[DD] is the only one in the house not sleeping with someone else-plus she's away from her mum for the first time as well [kinder]". Kinda makes sense but doesnt make things any easier.
We are most of the time trying to settle her back in her bed when she wakes, which works ok when i am not too tired. Plus, i can only do that twice a night usually and then im tired and grumpy and just want to sleep, so twice is usually the limit, sometimes 3 times and then it's eiother i jump in woith her of she comes in with us etc.. not ideal but i think we need to be not completely sleep deprived to tackle the resettling.
We used to use a reward type chart where she would receive a stamp and sticker in the morning if she slept through etc etc. but havent done that for about 2 months. might make another one this week sometime and see if that helps. we tried the dream fairies-they worked for a few days or so but then even a reward the next morning waiting in a special bag wasnt enough. I dont think [with DD] that it's something she can control. anymore anyhow. not sure if she could control it earlier on and now it's a big habit or what.
sorry for rambling on so much. i have held off posting in this section about her sleep habits for so long-usually just have a whinge in the country mum's board

there's probably a lot i have missed, and i am sure i havent given you much advice at all but hope it helps to know that there is someone else out there tonight with their wakeful child.
I have to say though, my DD is brighjt and happy, and doesnt seem to suffer too much till she banks up a bit of night waking then she seems to sleep for a longer stretch. then the night waking starts again. I think maybe she needs a few nights of good sleep to start up good sleep patterns again.
and also, my DD hasnt had a regular day sleep since about 19 months.
I am pretty tried right now so hopefully this post has mande some sense and it hasnt come out the wrong way.
Hope you get some sleep tonight!