If you haven't done so already, I'd say it's time to call Quicken Support on the phone and request help. Let them do a screen share session with you to review a download log file on your computer, to determine the nature of the problem and to figure out how to fix it.
Quicken Support:
jacobs said:There's plenty of history of differences in supported institutions between the Windows and Mac versions.
Vikas Bhatnagar said: So I checked with customer service and this is what they said - Axa Advisors LPL only offers web connect service available in Windows, the server is not supported in Mac. The situation is this, you might find the area where you can download a QFX or OFX file under on the broker or provider web site, but this file can be read only in Windows. You may try to import the file in Mac, but I don't guarantee if this will work completely because it might not be compatible.