Know exactly what you mean, Les. Often happens to me, I've got to be in the mood, or inspired, to write (novel), paint my pictures, or do some modelling.
Best thing is, have a look at some of the other projects on the modelling board, especially some of Wayne's shots from the Melbourne comp/exhibition, or his own work, and get inspired!
Then, pick up one small piece of the Dora, just to look at....then you'll be on your way!
Come on mate, let's see that wonderful bird of yours grow!