Omniscope enforces data typing as a basic form of input validation. If Omniscope sees (or you declare) that a field (column) data type is numeric, Omniscope will not let you enter text, or a date, etc.
To check and (if necessary) change the data type for each of your columns, go to Data > Manage fields on the Main Toolbar. From here you can change the data type of fields.
If the title or column header is blue, it means the column is a formula field and will not accept direct input.
Some fields which are not editable can be seen when using Connectors or Folder of files/images bulk re-naming/tagging features.