I'm not exactly sure if I understand what you're trying to do, but you should, from the event properties, drag the event diamond (not sure what it's really called) from one end to the next, which will cause your effect to start or end differently.
Explanation: I have 130 random 'regioned out' events (open in trimmer, select interesting/good part, region) on the timeline. I find a region that comes toward the end, I would like to send it to the end rather then having to drag it 40 minutes. This seems to get old after the 30th time.
It's faster to move it by selecting the event, then Ctrl/X to delete and copy into buffer, scroll and place the cursor where you want, then Ctrl/V to paste.
You can even eliminate the scrolling by using well-placed markers, which you can instantly pop to with the number keys (on the main keyboard).
One way is to highlight the Event, Ctrl X to Cut, Ctrl Shift F to Ripple the Gap away, then place cursor at end and Ctrl V to paste.
If you do this a lot, it sounds as if you are dragging your saved Regions to the timeline a little prematurely, or you are not first sorting them. If you give them names according to the order you want them, then sort by name in Vegas Explorer, you can drag them in that order to the timeline.
Yeah, I have been thinking of reworking my method. Like to randomize a couple of times to make the picture montage random, but there are 15 events that I want in semi sequence in the mix of the random pix.