It is possible to display UV traces by selecting them on the MS Browser and then clicking on the 'Open new Chromatogram' icon 
. From here you will also be able to select a range in the wavelength:
Here you can see the result of having extracted the trace at 254nm: 
And here you can see the result after having extracted the Total Absorbance Chromatogram: 
From the PDA-Total Absorbance Chromatogram, you will be able to extract the complete UV spectrum. To select a UV spectra: the dataset must have the full UV spectra set (and not just a single or a set of UV chromatograms, ie, MS browser panel must show a sub-item called DAD under the Traces item). Using the crosshair mode and clicking on a UV chromatogram while holding Alt pressed, will display the UV spectrum for the clicked retention time. 
You can also Co-add UV chromatograms by clicking and dragging the crosshair to select a range on DAD chromatograms as you can do with the TICs. Download the files used at this tutorial.
