You can manually Preview certain files but...
 

In case U dunno...

You CAN manually preview Some .xlx files(media files in particular) can be previewed by opening them using standard windows media player.

HOWEVER, there is the catch that if u have a lot of files in your temp dir, it will be hard to identify which file u wanna preview(As xolox simply names them as JOBxxx.xlx)

I wish these temp files are programmed to use the actual names, so distinguishing them will be easier.