Any time you train a table interactively, complete the required training first and then manually verify the table.
Brainware Table Extraction can train line types and column mapping for each type of line.
When working with interactive table extraction, learn the lines before you map the columns.
Because of the way interactive table verification works, you cannot manually delete data from a cell. Rather, if you want to discard cell data, unmap the column and re-extract the table to remap the column. Although it will seem as if you deleted the data, the data is still be there until you unmap the column.