We stayed at Cradle Mountain for a couple of days in 2013.
There are a few places about stay but I reckon the most convenient is Peppers Cradle Mountain Lodge, on the Cradle Mountain road. This accommodation is the closest you can get to the national park. It is then about 5.5 km through the wilderness park to the Ronny Creek Carpark at Dove Lake. There are a couple of disabled parking spots and disabled toilet at Dove Lake. Because the weather was great, we drove in our accessible van to the lake and I walked back along the road in my power chair. There is a shuttle that goes back and forth every 10 minutes or so but it was not yet wheelchair accessible in 2013.
There are a few paths from the car park to Dove Lake. The path is pressed earth and would probably gets pretty sticky if it was raining. Once you get near the lake steps appear but all in all it’s quite pretty.
There are extensive, wonderful raised timber paths 4 km throughout the park but they are not accessible for wheelchairs. Just inside the park entrance near Cradle Mountain Lodge there is a big car park and a visitor centre. The Dove Lake shuttle leaves from here. There is a wheelchair accessible walk here called the “rainforest walk” which is actually really great. Check it out.
As for the Cradle Mountain Lodge, it was quite nice. Wheelchair access was a bit clumsy but we got by with a little help from my trusty portable ramp. There is an accessible Cabin near reception which looks partly onto a road and partly onto staff huts but it’s ok. The roll-in shower is also okay and the hot water is good. There is a remote-control fake-wood gas heater (the other cabins have real wood, I believe). Some punters might find the whole place a bit expensive. We ate at the restaurant one evening, a huge fish n chips & lasagna and a crappy local Riesling.
There are a few nooks and crannies about the place you can get to in a wheelchair if you explore a bit, including a nice terrace at the back of reception.
Just near the Dove Lake car park there is a path up to the “Waldheim cabins” which has some lovely views. There is also a Tasmanian devil tourist sanctuary near the lodge called devils@cradle. I wandered up there in my chair but I’m pretty sure it’s not very accessible.