BaseElements requires the Database Design Report ( DDR ) to get the data that it imports.
The DDR is generated by FileMaker Pro Advanced and is a complete documentation of all of the elements in your solution. We use this report and tranform it into useful data which we then import into BaseElements. Without this report, and thus also without a copy of FMPA to generate it, you can't run BaseElements.
Generating the DDR
Open a copy of all of your solution files in FMPA and then go to the Tools menu, and to "Database Design Report...".
In the dialog, make sure all of your solution files are checked ( default ) and all of the options are checked ( default ). Change the Report Format to "XML", and you can also uncheck the "File Handling" checkbox. Click Create and choose a location to save your XML files to.
The name of the report isn't critical, although it's simpler to just leave it as the default ( Summary.xml on English platforms ).
The location of the XML files also isn't critical, although BaseElements does write to the folder containing the XML files, so you do need read and write access to that folder.