You can view the GEDCOM files that were input. Normally, this is not something most people will want to do, but the capability is there if you want to track down some of the warnings Behold may be reporting.
To view the files, you can either select "View GEDCOMs" from the View menu, click on the GEDCOM file icon on the toolbar, or press F10. This will display the input files using the default program for text viewing for your computer, as shown above. If more than file was input, then all of them will be displayed.