Do I have to tape the ceiling were the durock meets because I am tilingfloor to ceiling

I'd recommend it... and use a mesh tape.

robertjag does not find this helpful : do I use joint compound or thin set

Congratulations Einstein...

You violated the site rules. You did read them didn't you? My answer was factual based on the question YOU asked with the information YOU provided, or more like didn't have the common sense to ask... YOU violated rules pertaining to not helpful.

Since YOU never asked that question... YOU implied you KNEW that much.

But since I'm not helpful according to you... I'm not answering you. I hope nobody else does either.

I don't like RUDE people.

The quality of your answers is directly related to the quality of information you provide in the question.