The DELETE statement conflicted with the REFERENCE constraint "fkey$xxxxx$xxx". The conflict
occurred in database "DATABASENAME", table "dbo.TABLE", column 'COLUMN_NAME'..
This type of error when using Test to Live is normally seen if there has been design change in the Live Environment that are not in the test environment.
Solution / Workaround:
First you have identify what the changes are. The clue is normally in the table and column names in the error message.
If you have a reference list , category, ordered list etc you can compare the tables in the DB.
FROM [Live].[dbo].[im_incident_category] where im_guid not in (SELECT im_guid
This would give you a list of the items that are not in Test.
Once you have found items that are missing you can Design Transfer them into Test.
Please see the following for more information on Design Transfer, https://help.landesk.com/docs/help/en_US/LDSD/7.8/Default.htm#../Subsystems/Designer/Content/WelcometoDesigners1/Exporting_items_from_you.htm?Highlight=design%20transfer
Please Note the comparison for test to live is done by GUID and some of the named attributes may exist but have different GUID's in the case of Data Imports.