The keyboard widget is casting 16 bit hex value into an 8 bit char, losing the leading byte. The character that appears on the '5' button is currently a 'G' (0x0047). It should actually be a '?' (Capital N with caron - 0x0147):

Qt Code: 
  1. // Create keyboard
  2.   //
  3.   // Note: The hex numbers here are unicode code points, not
  4.   // extended ascii or utf-8 encoding.
  5.   //
  6.   QHBoxLayout* row1 = new QHBoxLayout();
  7.   createBtn(row1, 2,  '1', '_', '1',  '!',                     static_cast<char>(0xBC));
  8.   createBtn(row1, 2,  '2', '%', '2',  '@',                     static_cast<char>(0xBD));
  9.   createBtn(row1, 2,  '3', '&', '3',  '?',                     static_cast<char>(0xBE));
  10.   createBtn(row1, 2,  '4', '(', '4',  static_cast<char>(0xFF), static_cast<char>(0xB0));
  11.   createBtn(row1, 2,  '5', ')', '5',  static_cast<char>(0xDF), static_cast<char>(0x0147));
  12.   createBtn(row1, 2,  '6', '-', '6',  static_cast<char>(0xE0), static_cast<char>(0xC0));
  13.   createBtn(row1, 2,  '7', ':', '7',  static_cast<char>(0xE1), static_cast<char>(0xC1));
  14.   createBtn(row1, 2,  '8', '/', '8',  static_cast<char>(0xE2), static_cast<char>(0xC2));
  15.   createBtn(row1, 2,  '9', ',', '9',  static_cast<char>(0xE3), static_cast<char>(0xC3));
  16.   createBtn(row1, 2,  '0', '.', '0',  static_cast<char>(0xE4), static_cast<char>(0xC4));
  17.   createBtn(row1, 3, false, Qt::Key_Backspace, "<---");
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Has anyone ran into something similar?