I did encounter an issue similar to what you describe on 9.2.1.208, but the workaround I described worked for me.
You must make sure that version 8.0 is selected AND copy + paste the legacy fingerprint; just doing one won't work.
If you have access to the SQL database, the query to fix it is simple (but backing up your DB is always a good idea):
USE [yourLFDSDatabase]
GO
UPDATE [dbo].[hosts]
SET [fingerprint1] = 'yourlegacyfingerprint'
WHERE [name]='yourmachinename'
GO
To see if it's set correctly:
SELECT [id]
,[name]
,[fingerprint1]
,[fingerprint2]
FROM [yourLFDSDatabase].[dbo].[hosts]
You could also try going to the "Machines" tab and completely removing the machine, then re-registering your application(s).
I think this issue may also be present in version 10, so we'll look into it and aim to include a fix in the next service pack.