I haven't tried it, but in theory..... To crudely simulate a velocity envelope, split the section you want to slow down then speed up into similar sized (very short) events. Then right click on each event, choose properties and progresively change the Playback Speed down then back up.

Changing the speed via the Properties gives you better control over just doing a Ctrl-drag on the tail end of each event.

Not fun but should give you the desired effect. I'm not familiar with any plug-in that would do this for you.

Added: Oooh, a thought... download a trial version of Vegas Pro, use the velocity envelop on your event, render it out then bring the resultant file back into VMS.

Thanks for those replies, I will download pro and try that.

In peoples opinion, what are the main advantages of pro over VMS?

The single biggest advantage used to be unlimited tracks but now that the studio version has 10 of each that's probably more than most people will ever need.

http://www.sonycreativesoftware.com/moviestudiohd/compare

It has 5.1 surround sound. The advanced color curves are really nice for recovering under/overexposed images, way better than anything the studio version can do. Keyboard trimming is probably something you'll wonder how you ever lived without, and once you've used it you'll probably detest the studio version. It allows you to tweak all the MPEG custom parameters while rendering.

There are tons of other features, some listed in the comparison chart i linked to above. I've mostly mentioned the ones that are important to me.

MSmart :

Did you notice any rendering problems when using Ctrl + Drag to slow mo a video clip in VMS 10 P ?

I tried it on several clips and ended up with a very stuttery slo motion clip. Not smooth at all.

Kelly - VMS now allows customisation of MPEG settings too.

For me, I'd say the most important things missing are compositing modes, and 3d track motion, and I occasionally fire up my Vegas Pro 8 for the masking, otherwise I prefer VMS10.

Some features in Vegas Pro that I use on a regular basis that Platinum 9 didn't have are:

-unlimited video tracks. BUT Platinum Studio 10 has 10 video tracks (one of the primary reasons I upgraded from Vegas Platinum 9, it only has four tracks)

-masking. Much more powerful tool than cookie cutter. I was getting around this when I was using Platinum 9 by making my own masks w/ Paint Shop Pro using white shapes on transparent alpha channel background. I still sometimes make my own masks and use in Vegas Pro 9

-3D track motion
-advanced color selectors and adjustments.
-velocity envelope.
-ability to run scripts

IMHO, Platinum 10 is plenty powerful now to do most videos and has a deshaker filter which Vegas 9 doesn't have. I dont see any reason to really upgrade to Vegas Pro 9 unless someone really NEEDS one of those features mentioned above.

To add to what has been said:

I downloaded the VMS 10 trial.

Things I appreciate: Image Stabilizer, preview enhancements, better handling of point-and-shoot files, layout improvements, slideshow creator.

Things I miss from Vegas Pro: Scopes, velocity envelopes, unlimited tracks, scripting, 5.1 panning, audio monitoring and busses, automation, nesting,

This is the long way of saying I can't wait for Vegas Pro 10!

@eightyeightkeys,

I haven't tried slowing down a video yet, just speeding a couple up. They seemed to turn out okay.