I once tried the library idea. a therapist asked me to think about being in my local library reading my favorite books before I went to bed and then when in the nightmare imagine there is a library in my dream and go there and read.

I have also tried the therapeutic approach of rewriting the out come.

It didn't work. My nightmare is basically a memory of a situation that I repressed. When that memory happened I was not in a library so my nightmare does not contain even the idea of a library and because I am only dreaming what has actuallly happened I cant change the nightmare in any way.

As for rewriting the outcome it does not work for me because I only remember a small portion of the nightmare. I have tried to write what I would like it to be but that has not worked iether.

And the clock thing does not work for me because when there are any clocks in my dreams they are actually moving and telling time. Probably because watching clocks is sometimes what I did during abuse situations.