I think I found a method I like better.

Split the event on both sides of the single frame I want to freeze. Apply a velocity envelope to just that one frame and set it to zero. Stretch the split-out frame as desired.

RexA - Oh yes, very straight forward. I've done the still picture thing. The "stilled" single frame is almost the same concept. I do like your approach. Far neater and somehow more "Edity" - if you know what I mean - yeah?

Thanks for the tip,

Grazie

Yes!

A point i've tried to make a few times before is that the best editing method for *YOU* isn't necessarily the simplest, most straight forward, or the one that is most correct according to the authorities. The best editing method for you is the one that makes the most sense to you and that you are most comfortable with, even if it does take a few more mouse clicks.

Splitting out a frame may take a few more steps than applying a velocity envelope to the entire clip and setting points on it, but it is conceptually good because it isolates the task of creating stills to just those parts that you want as still. You don't have to deal with the velocity envelope on the rest of the clip so there's no chance of accidentally setting it to 99% or 101% without noticing it, because it's not there. You don't have to worry about audio sync because the audio remainsl in sync with the sections that haven't been stilled. Changing the duration of the still now becomes a comfortable and usual task of dragging out the length of the still frame event. With auto-ripple enabled, this is a nearly effortless process.

Yes, it's more steps and more events than just using one event with a changing velocity envelope across it, but if you can work this way faster and easier then go for it!

RexA
Your method of exporting a frame is in-elegant. Sorry. If you can live with the fact that action stops (and starts) abruptly, from 100 to zero in one frame, you could do this:
Select quantize to frames. Find the frame you want to freeze and split the event before it. Spli the event after it too. Drag that frame to an empty track above. Once there, insert velocity envelope and set it to zero. Pull the right edge of the short event out untill it lasts as long as you want it to. Move the right part of the long event (the lower track) until it begins exaxtly where the frozen one ends.
This is a very graphical, easy to do and easy to grasp method.

I imagine you know how to do the velocity envelope thing on just one track. Let me just remind you, for the benefit of the many people who don't. It is just as easy as the method above, and you can get the motion to slow down or speed up gradually, which at least looks more professional.
Vegas will calculate for you the length of the event after you have slowed it down, so don't worry about that.

Insert velocity envelope on the track.
Find the first frame you want to freeze.
Add a point there. Add another point a few frames before that. The distance between them is the slowing down period. Make it as long or short as you wish. Because of the slowing down you will have to move the point you first made, a little to the right, because that exact frame now appears a little later. Practise will make you good at hitting the right spot quickly.
Now you set a new velocity point at the place on the timeline where you want the action to start again and one where you want it 100%.
Pull the right edge of the entire event to the right until Vegas tells you it has reached its new length - marked by the little triangle appearing at the top edge. You are done with the first freeze. On to the next.

TorS, RexA's method is the same as your first method, except all in one track. As you point out, it is very graphical and easy to grasp, but the second track isn't necessary. Your second method, while simpler in steps, may be more difficult to grasp and has the added difficulty in that it does not preserve audio sync.

Thanks for the comments everone.

Just thought i'd mention one little shortcut that some may not be aware of. If you make a selection on an event (drag or set in/out points) and then hit the 's' key, it splits on both ends of the selection. I had been manually splitting at my two desired ends when I accidentally discovered this feature.

Good. Thank you for mentioning it.
Tor

The other hotkey I found that is now becoming invaluable to me is the 'u' and 'g' keys. It always bugged me whenever I split something, if I wanted to adjust only the audio, the video track moved with it. But now I've found that 'u' ungroups the audio track from the video, so now I can move it wherever I need it, and the video track stays put. That's my latest happy discovery :-)

Rogue One