When using K66 to set up 180 MHz high speed mode the SMC->PMPROT register must be set to allow high speed mode. In KSDK 1.2.0 system_MK66F18.h sets SYSTEM_SMC_PMPROT_VALUE to 0. Since this register is a one time writeable after reset it is not possible to change this.
Basic objective should be that Processor Expert clock configuration should be possible to use also for high speed mode.
Realized that this is a processor expert question only...