we have a TRK-KEA128 demo board with a PKEAZ128MLK chip. The board has a external crystal (Y2) which is conntected to PIN 13 (EXTAL) and 14 (XTAL). The cyrstal is not in the documentation but physical on the board. Unfortunately the crystal is not working if ICS mode FEE is selected. My project is a minimal Processor Expert Kinetis Dev Studio sample with CPU Bean, 250ms Timer Bean and LED Bean. The LED is toggeled with the timer event. The project is doing fine if ICS mode is FEI.