I need help in high school setting!

[bmwriter]

Hello, I have to teach Pro Tools in high school.
But I can't use the sound from the keyboard in Pro Tools.
I have 14 computer stations in the classroom.
I'm using pro tools 10 on windows 7 32-bit for all the computers.
I have Korg X50 keyboards and they're connected to the computer via M-Audio Uno USB interfaces. I have no problems using virtual instruments. I can play on the keyboard, record midi data in pro tools and hear sound.
Which means the controller side of the keyboard is working fine. It's the module side of the keyboard that I'm having trouble with in Pro Tools.
However, when I create a midi track and set input and output to X50 keyboard to use sound from the keyboard, the pro tools recognizes the keyboard because I can see the meter moving everytime I play something. I can also record notes but don't hear any sound during recording or after. I've been working on this for a few days and it drives me crazy. If anyone knows how to fix this issue, please please help me out. Thank you very much in advance!

p.s. Another thing! I can't find patch list for this keyboard. Do you know where I could get it?


Now, I installed Korg X50 editor driver to see if that solves the problem. And I get two messages everytime I open PT.

Here's the first message.
Pro Tools: ProTools.exe - System Error
This program can't start because MSVCR70.dll is missing from your computer. Try reinstalling the program to fix this problem.

After that, I get this.

Move Unauthorized Plug-ins
Pro Tools could not load the following plug-ins either because no valid authorization could be found, the iLok key was not connected or the plug-in was damaged.

X50 Plug-in Editor.dpm


Now I'm guessing I should use X50 Plug-in on trk to use sound from X50 keyboard.
I think I'm supposed to see X50 plug-in under instruments where there are Xpand2, Boom, Vaccum, MiniGrand. I don't see that.
Am I right about this?
Any help would be really appreciative.