Hi @altatke
Hope you are well and thanks for your patience.
I would like to share with you a thread of our community using other Kinetis, but it is being used Processor Expert too, so this thread might be very helpful to solve your concern about entering to a low power mode in your Kinetis, almost at the end of this link you will find a example code written by Kerry, so it can help you too:
https://community.nxp.com/t5/Kinetis-Microcontrollers/Processor-expert-10-4-MKL05Z32-how-to-configur...
In addition, we have another Application Note that includes best practices to use Kinetis in Very Low Power Mode. My suggestion is to follow this guide and take in consideration the necessary hardware on your board. AN is attached.
Hope the information is helpful for you, please let me know if you have more questions.
Best Regards.
Pablo Avalos.