You have two cares, apparently: functionality and presentation. These are of course good cares to have- yet you must decide which of the two is most important.
TypeAheadCombo will submit the <option> value, either if it is not enabled to accept new values, or if a new value is not typed. If a new value is typed, there's only one context which must be dealt with: the new <option>'s text, which is set to the same as the value, as the typing happens.
If your primary concern is a flashing cursor, I'm sure somebody can come up with a way to add one in to the TypeAheadCombo class.
Here's a quite complex form with TypeAheadCombo in action, and the instantiation is (of course) no more difficult than ever: http://www.10mar2001.com/temp/formUI/index.html
. There's no form too complex for this script.