Hello Richard,
Do you have two FRDM-K22 board ? If you have , please connect the two board to test.
I have test the DSPI demo of KSDK1.2, it can work well , i refer to the DOC of "Kinetis SDK v.1.2.0 Demo Applications User's Guide.pdf" (under here :\Freescale\KSDK_1.2.0\doc) to connect the pins :


then i can see the result at putty :

So the demo code with no error. The reason why you not the the spi signal is the MASTER only send
once for the project , so the oscilloscope can not catch it or we can not see it . You can try to change the
code to make MASTER board send data for while , then it can see in the oscilloscope.
Hope it helps
Alice