If you need to revert to a backup copy of the Tascus application, do the following steps:
Open the Tascus folder
Right-click on the Tascus icon on the desktop or Start menu, and select Open File Location
The Tascus folder should in the following location:
Find a Backup & Extract It
Open the Backups folder, this will contain zip's of previous versions of Tascus before updates were applied.
Find the date of the backup you require, right click and select Extract All...
Delete all existing Tascus files
Go back to the Tascus folder, and delete all files (excluding the Backups folder)
Replace with the backup Tascus files
Copy the files from the extracted backup folder
Then paste into the Tascus folder.
This should leave you with a restored older version of Tascus.
You can now restart Tascus, ensure that if prompted, you do not accept any updates.