Just upgraded from PT7 to PT10 this weekend and from Windows XP to 7. Ptulz would recognize the Tascam 2400 mixer/controller and would control Ptulz BUT the Tascam would not receive information to light buttons, move faders, etc. I found that the Ptulz Windows 7 optimization listing below fixed the problem.
Of course you need to go into your midi controls and make the correct HUI assignments for each of the 8 channel banks.
Run as Administrator
This can help with various launch issues as well as a variety of MIDI issues (i.e., no MIDI output or control surface communication) and using the Avid/Digidesign hardware driver in third-party DAWs.
•Right-click on the Pro Tools icon on your desktop.
◦If using a third-party DAW, right-click on that application's icon instead.
•Choose Properties.
•Click on the Compatibility tab.
•Check the box that says "Run this program as an administrator."
•Click Apply and then OK.