OK, I've searched again my sources and I found a definition of window["cr_getC2runtime"]. I guess something in the plugin stop that line from being interpreted. I wonder why the substitution of cr_ for cr. in the source made my project work, not only as standard html5 but as chrome extension, too.
I have checked with another project I had exported in the past and it seems to work with just 4 typeset exceptions, so the wrong part should be in the plugin. In the new project, I see no functions defined as "cr.getC2runtime", so I guess they do nothing and return null. How could my hand-edited project work?
I used many nested "Pick all" conditions. Could it mix something?
Just in case you want to compare how they run, here they are:
1) my "Jigsaw Puzzle", as originally compiled: http://www.apagada.com/varios/jigsawpuzzle/index2.html
2) my "Jigsaw Puzzle", cr_ substituted by cr. http://www.apagada.com/varios/jigsawpuzzle/index.html
I just tested both and now both of them run. I wonder how or why.