I have this file (PHOTOSHOP CS 5.1):
I have installed:
How do I use? Where do you have installed?
What is the name of the extension?
Usually after you install those kind of extensions with the Extension Manager they are listed under Window>Extensions in photoshop.
Most are panels.
Yep. As advised above, if you can see it in extension manager, and it is checked as Enabled, it will appear under Window > Extensions and can be launched.
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