WP Edit Pro Version 4.0.1
A new version of WP Edit Pro was released today.
This update is primarily a maintenance release. In the excitement of the new features for multisite environments; I forgot to enable debug mode when single site testing (which got little attention).
Some of the functions used in the new code for multisites; is only available when the plugin is network activated. If it is not network activated; the functions are not available/defined; resulting in the errors we have seen.
The full list of applied fixes for this version can be found on the Plugin Changelog.