Yes, I have tried to set Cursor = Cursors.WaitCursor as well, it gives same result as UseWaitCursor = true.
It affects only some small areas around worksheet cells.

I'm not trying to determine that application is busy, I just want to do something like this:

ultraSpreadsheet.UseWaitCursor = true;
try
{
    //some long operation
    }
    finally
    {
    ultraSpreadsheet.UseWaitCursor = false;
    }

Hello Oleg,

Thank you for the update. Setting the protection on the worksheet would prevent editing.

Thank You!
CursorFilter do the trick!
But only when UltraSpreadsheet.Enabled = true.
When control is disabled, BeforeSetCursor(..) method is not triggered and it still shows default cursor.

I used Enabled property to prevent any user input, but I think the same might be achieved with workbook and/or worksheet protection, am I right?