In a table with a column called "COMMENT" - (quotes included), the following error appears when right-clicking in the data grid and selecting 'Create INSERT for all rows' and pressing OK to generate the script:
ORA-01741: illegal zero-length identifier
This is due to this one particular column name, but the same actions above work OK in Toad 9.0.1 and 8.6.1 with the same table & column.
Issue fixed in version 9.5. The latest version of Toad for Oracle can be downloaded here.