Diagnosis
The SPUMG scan "Tables with Ambiguous Language Information" foundrecords which use the character U+0000 as language key. You tried toassign a code page to the language by inserting it into the SPUMGLanguage List.
But the language U+0000 cannot be used in the Language List because thescan "Reprocess" uses a dynamic where condition for the table selectionbased on the contents of the Language List. In dynamic where conditionsthe character U+0000 must not be used.

System Response
All other languages you marked in the "Invalid Language List" have beeninserted into the Language List.

Procedure
You can insert the language U+0000 into the "Ambiguous Language List"and repeat the scan "Tables with Ambiguous Language Information" for theaffected tables. Then all the words using the language U+0000 will beinserted into the system vocabulary.
You can also continue without repeating the Ambiguous Language Scan. Thescan Reprocess will find all the records using language U+0000. Therecords will be inserted into the "Reprocess Log". In the Reprocess Loga language can be assigned to the records.
In general only very few records are affected. Therefore it does makesense to continue the preparation without repeating the scan Tables withAmbiguous Language Information.