I think I've seen others express problems with trying to use a mapping elsewhere within the pseudo-constructor, so you might want to try avoiding that.
I'm guessing this is related to a previous thread on this forum where you talked more about your myConfig process. I had done something similar in Application.cfc myself (albeit without a CFC file). I read in an XML config file in the pseudo-constructor, parsed it, and inserted the "this" variables. I then read the same XML file again in the onApplicationStart method and parsed out the "application" scope settings and inserted them. Eventually I moved all the "this" stuff out of the XML file and hardcoded it in the Application.cfc file. Why did I do this? Because the pseudo-constructor is run on every request. So on every request, my application was opening and parsing the XML file and rewriting the "this" scope, all of which added unnecessary overhead to my application.
HTH,
-Carl V.