When posting Sales Invoice with Cronus (BE Version) and you get this error :
Error message "You must specify Journal Template Name in Gen. Journal Line Journal Template Name = '' Journal Batch Name = '' Line No. = '0'
Then, check the Inventory Setup > General Tab > FLD Jnl Templ. Name Cost and FLD Jnl Batch Name Cost.
If empty, fill in both fields.
That's it.