I hate when applications seem to know more than you do but won't let on.

You can get your Serial Number of your Xara Desktop application (XDA) using the HotKey Ctrl+Shift+Alt+1.
All well and good. The XDA has to be running and the result can not be copied.

The following setup for Notepad++ > Find in Files works for all your installed XDAs:
  • Find what: string=
  • Filters *.*
  • Directory: C:\ProgramData\Xara.

The result can be copied off and saved for use later.

Manually, you can navigate to each XDA's installation_x64.ini or installation.ini and open it instead.

If you use Find what: NumberOfStarts=, this returns the number of Runs each XDA has made.

Acorn