The ‘start’ and ‘end’ pan time sliders would normally adjust that type of thing. I am thinking though the reason you are getting a pause just before the transition stage is because your computer is loading in the next photo which is taking the time. This can sometimes happen when just previewing your slideshow depending on how fast your computer can load pictures in. When you preview your slideshow for the second time you may not get the pause as your pictures will still be loaded in memory.
When you come to create the DVD or video file, this pause will not be there. It maybe worth trying this in a test video file and check that this is the case. Select ‘output type’ to ‘video file’ at top of screen then select create video.
If not this could you email you project .pds2 file and I’ll investigate further. email@example.com