On what computer operating system is your Premiere Elements 12 running on?
Edit/Zoom only one section of a whole clip....that introduces the concept of keyframing and specifically keyframing the Scale property under Applied Effects/Applied Effects Palette/Motion Panel expanded where you can find the Scale property (for Zoom) and the Position property (for Pan).
There are also way of keyframing at the video and audio clip's rubberband level.
Provided there are no clips above or below that particular area which would interfere with the process, right click the gap, click on the resulting "Delete and Close Gap" pop up. There is always the consideration of closing the gap using the mouse curse to click and drag the clip over to close the gap. There can be problems...
What exactly do you mean "switch between tracks"? The content on the upper track will be what is seen in the monitor unless there are transparency in the file. You open the track, select it contents, and work away. I suspect that you have something else in mind, so please give more details on what you seek in this regard.
The problem with closing gaps with the mouse delete close gap is that I want
to close ALL gaps in the entire movie. Secondly, if the audio video are
unlinked, and there is an audio clip running underneath, on the audio track,
the command is disabled.
So I am looking for new tricks (like in final cut, it can be done for the
Sorry, no new tricks for Delete Close Gap in Premiere Elements as it applies to closing all the gaps at one time.