COMPC is for building libraries. It does not generate an entry point. MXMLC is for building applications.
So, IMO, you would use COMPC to compile all of your library code and GCC to generate a single file, then you will have to build your own index.html and main.js that calls into that single file. You can try using MXMLC to generate the index.html and single file, but it will want to output goog.requires. I suppose you can manually edit the results. You are not using the kind of workflow we support, so you will have to manually perform some of the steps. -Alex