Map tries to calculate a "common prefix" between the pagespec and the page being rendered, and then later does some substitutions using the prefix. But the path has /'s in it and the common prefix doesn't, so it never matches correctly. So, add the /'s.
Map tries to calculate a "common prefix" between the pagespec and the page being rendered, and then later does some substitutions using the prefix. But the path has /'s in it and the common prefix doesn't, so it never matches correctly. So, add the /'s.