Hi Danny,
I've managed to solve the problem since. But I 'uninstalled' the RT softwares by booting up the PXI in Windows (yes, my controller is a dual-boot system), and removing 2 files in C:\ and the entire folder C:\rt. Then I re-installed the softwares using MAX, and it seems to work now. (I managed to get a NI-rep from S'pore to help me with this as I needed it to work urgently). Thanks for replying though!
Cheers.