In Compare Schema, the dialog box to save "Schema Definition File" is grayed out. The script is being partially (only the header comments until the first line "Set define off;" is included) saved when a file is specified in the Sync Script dialog box. After Compare Schemas has completed, all other options except Print on the Sync Script tab are also disabled.
In the sync script, the following comment is added:
"Note: Synchronization script is complete and usable in the commercial version of Toad when the DB Admin Module is present."
'Sync Script' ,'Move Script to Editor' and 'Create Schema Snapshot File' is only enabled if an Xpert or 'DB Admin Module' add-on key is registered. Go to the Help menu | Licensing and ensure you see the 'DB Admin Module' add-on in that screen. You can also change the license key in that screen if you have another license key that has the 'DB Admin Module' add-on in it.