I am using version 1.5.1 (with pro 30 day trial plugin installed) and no other plugins enabled.
When editing the settings in the "Settings" section, I enter a URL for a flower affiliate in the "order flowers" section, then I click "save" and it returns an "It seems we can’t find what you’re looking for..." error message.
hxxp://mysite.com/wp-admin/admin.php?page=wpfh-settings
I do not get this error if that line is left blank.