DAB 12.3 What files are used upon creation of app

Dictionary App Builder
1

L.S.
Several style additions to the “modification” tab do not to seem to result in a change in the app, which led me to question the actual files that are being used. So, possibly a superfluous question, here it is anyway:

I would like to know what files DAB 12.3 uses upon creation of the app. Here is what the appdef file states:

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image1789×210 53.8 KB

At the !!DAB_SOURCE location the following files are present at export from flex:

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image250×149 4.46 KB

At the project location I find these files:

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image335×187 6.05 KB

So, upon creation of the app, what files are used?

And secondly, what exactly happens when the button “update from source is selected”? Are both the .xhtml and css files from the source location imported ? If yes, are the local XYZ_data files in the project folder updated with .css and xhtml data from the source location?

Thanks in advance for your help.