Hello @Karlygash,
ok. Maybe I got it now. You shouldn’t use Column Appender node in this case but rather Cross Joiner node to get max record id you obtain from GroupBy node in every table row from RowID node. However if you use Column Appender then you can use Missing Value node together with option to populate missing values with previous value. Hope this helps!
Check this topic regarding Alteryx to KNIME:
Br,
Ivan