If you want to use lookup, blacklist or whitelist with an external file, you need to create a filemap in the maps:
<maps>
<filemap name="xyz" file="c:/git/metafacture/xyz.tsv" />
</maps>
<data source="litA">
<whitelist map="xyz">
</data>
It would be great if it could work like lookup in FIX (metafacture/metafacture-fix@283075c) were you could use the attribute in= to straightly reference the external file.
<data source="litA">
<whitelist in:"c:/git/metafacture/xyz.tsv">
</data>
So that you do not have to create a maps collection everytime you would use a list just once.