I'm not a big fan of ttw editing, but i tried it anyway ..and doesn't work.
It seems that at some level, filesystem files always wins against ttw ones.
I recreated the exact folder structure, but here's what i see for every step:
<PersistentResourceDirectory object at /Plone/portal_resources/resource_overrides/static/components>
<FilesystemResourceDirectory object at components>
<FilesystemResourceDirectory object at tinymce-builded>
And from now on, filesystem resource directories wins over ttw folders so i can't reach my custom resource