As for your issue, the best I can do is suggest that a verbose (command-v) boot may tell you something.
Actually I did do that...just forgot to mention it....but couldn't make hide nor hair out of the information.
Jumping back to square one, perhaps some of what meant nothing to you will mean something to somebody else.
Is there anything you can post? (If there's too much to remember, you can photograph your screen, import the image, upload it to a remote host, and link to it.)
