There is a bug in macroexpand functionality: it fails to macroexpand (using C-c <ret>, for example) a form when the point is at the end of the last line of the buffer. Add a newline, or even a space, and it works.

To reproduce: In a lisp source buffer, go to the last line in the buffer, type '(+ 1 1)' and now, without adding anything and with the point after the close parentheses, macroexpand it. If there is a line after the line with (+ 1 1) form, it works.

Marco