It helps to answer if you indicate the version of Captivate you are using.
If it is CP4: select the object on the stage and use Enter. This will open the Properties dialog box.
If it is CP5: the Properties panel of the selected object is automatically focussed on when you select the object on the stage, could you perhaps explain why you want a shortcut? Because you are talking about 'styles' I think you are using CP5. Each object inherits the default style for that kind of object, as defined in the Object Style Manager. If you want to override the style, you normally change in the Properties panel. Perhaps I do not understand your question all right: could you please elaborate what you mean by attributing a shortcut key to a style?
Hopefully Lilybiri won't mind my offering up an observation here.
...If it is CP5: the Properties panel of the selected object is automatically focussed on when you select the object on the stage, could you perhaps explain why you want a shortcut?...
If this is Captivate 5, keep in mind that the workspace may be configured in a variety of ways. For example, the Properties Panel may be collapsed to icons as shown below:
Certainly when whatever object gains focus, it's there when I expand the collapsed panel. So my guess is that one possibility is mitpancha is asking if there is a shortcut for expanding a collapsed Properties panel.
According to the Window menu Shift+Control+D should open it. But that doesn't seem to happen here on my own setup. Not sure why.
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Great, Rick, to the point, forgot again that this is the Getting Started forum.
Did you see the double postings?
Indeed I did. I had to put on my moderator hat and delete the other thread.