Omar;
When you use the SCXI modeules at multiplex mode, all channels of all modules are being multiplexed to channel 0 of the DAQ board, so, you will need to connect only one SCXI module to the DAQ board and all the other modules can be read by the DAQ board. Then, you don't need any special mapping in order the DAQ board to see all the channels of your SCXI system. Take a look at the scxi User Manual, and search for the string which you can use to test each channel of your system in MAX->Test Panel.
Hope this helps.
Filipe