I don't think there is any problem. You can move it as long as you've have become the registered owner. 

I've move in to my house and it takes me 2++ months to chase the title out from the land office. If I would have wait for them, I would have sleep on the street for 2++ months.

Moving in & stamping(think u meant register) of transferred documents are 2 different issues . So long the seller let me move in, I see no reason why I should not. Just make sure u inspect the house upon vacant possession. You are already at the final stage.

U can even take possession way before that if the seller is willing to do so. There is no law saying that u cannot.
However, it is best not to do renovation.....what if it cannot be transferred for whatever reason.

just my 2 cents