Select Add under the Datasets menu to bring up an interactive file window. Locate the file you want in the file list. Note, that double clicking on the .. entry in the Directories list will take you up one directory level. Double clicking on directory name will take you down into that directory. Select the desired file name and click on the Select button to open it. You may open one or more files. Click on the "Cancel" button to close the File Dialog Window.
Now select New under the Windows menu. A dialog box will pop up. Enter a desired window name and select the OK button. A spectral window will open up. In that window, press and hold the right mouse button to bring up a menu. Select the Attributes entry. A spectral attributes window will open.
In the spectral attributes window select the Dataset menu entry in the "File" menu. Another popup will appear listing all the datasets that you have opened. Double click on the desired filename. Now type in appropriate values for the Level and Mul fields in the attributes window. Selecting the Draw button at the top right corner of the Attributes panel will generate a contour plot of the spectrum.