Under Lion, unable to log in with DisplayLink drivers installed I have a mid-2009 MBP 15", and I recently upgraded to lion.

I also have DisplayLink hardware which worked fine under SnowLeopard.

With Lion, as per http://www.displaylink.org/forum/showthread.php?t=1059, I am unable to log in, ever, once I install the DisplayLink drivers -- even if I have none of the DL hardware plugged in. I had to reinstall Lion to recover.

The forum thread suggests turning off 'automatic graphics switching' as a workaround. 

I could flip that setting and then install the drivers and reboot again. If it doesn't work, however, it's another Lion install, which is quite time-consuming. Is there some mechanism I am missing that would allow me to recover my system more rapidly if the workaround is unhelpful?
I have this problem as well.  However, I discovered that I WAS able to log in - the issue is the login prompt (and later some window content) was not displaying.

Once I plugged in the displayLink display, I was able to uninstall the driver.  However, the displayLink forum says this is due to a Lion issue with video drivers covered in this thread:  http://www.displaylink.org/forum/showthread.php?t=1059

So this needs to be address; I am out a display until this is fixed.