Got a table with some not null columns. When checking the script tab (in schema browser | table | script tab on right) all the columns show up as null. However, the column tab does show some not null columns.
Even though creating all columns with the NULL keyword, the columns defined by the primary key do not allow nulls. The Columns tab shows info from USER/ALL/DBA_TAB_COLUMNS. The script tab creates the table as originally created it. Toad is working as designed.