INS key does not enter Insert mode, Ctrl+R works fine

[JDoucette]

Version: PC-BASIC 2.0.7
Repro: Press INS key on a NumPad with the NumLock shut off. SCREEN mode doesn't matter.
Expected: Insert mode is activated, and cursor changes to half-height. Typing then inserts into the current line.
Actual: NOP. Typing continues to overwrite characters.
Note: Ctrl+R does enter Insert mode with cursor at half-height. Typing will insert into the current line.