Didn't work for me either.
Using Window 7 64bit
Have reloaded Roxio Creator 2010 Pro. Loaded pxengine4_18_16a
No Lower or Upper filter problems.
Every other program in the world can see my drive had the same problem with Creator 2009.
Will not be getting 2011 unless Roxio sort out this problem
What realy confuses me is why it works for six months and then stops working.
This is identical to what happened with 2009