This Boolean parameter specifies how the commonly used keystrokes for copy (ctrl+c), cut Ctrl+x) and paste (ctrl+v) are processed.

0 = process normally (via the appropriate .DIN file)
1 = pass untranslated to the host application

The UseXCV parameter is defined for the IME in the Registry section HKEY_CURRENT_USER\Software\Dyalog\UnicodeIME\

When UseXCV is 1, the keystrokes Ctrl+X, Ctrl+C and Ctrl+V are passed untranslated to dyalog.exe which treats them as CT, CP and PT respectively. This is likely to be true for other host applications using the Dyalog keyboard.

The standard Dyalog keyboard (*.din) files map Shift+Del to CT, Ctrl+Ins to CP, and Shift+Ins to PT. These will therefore work independently of the UseXCV option.

The standard Dyalog keyboard (*.din) files map BOTH Ctrl+X and Ctrl+Shift+Xto So if UseXCV is set to 1, you must use Ctrl+Shift+X to obtain . Likewise for C and V.