it's always nice to hear when an user enjoys the work with Embedded Wizard, thanks a lot!
I am not sure weather you would like to use a SPI interface for the serial output or to communicate with other hardware?
If you want to redirect the serial output of the print functions you can adapt the 'EwBspConfigSerial()','EwBspPutCharacter()' and 'EwBspGetCharacter()'. To make that conform with an SPI system you probably have to convert the characters to the binary sequence that you want.
Generally the Embedded Wizard GUI Project itself is completele hardware independent. Therefore you should take a look in 'Device Driver.c' and 'Device Driver.h'. These filese are the 'Connection' between Embedded Wizard and the rest of you code. There you should find 'DeviceDriver_PrintMessage' which directly will be execute when you press the button 'Print "Hello World"' button.
Anyway, unfortunately we do not have a dedicated example for that, but let's try to find the issue.
For that; could you please post more details what exactly is not working?
1. Have you seen our documentation about 'Platform Integration: Device Class and Device Driver'?
2. If your SPI code produced delays within the Embedded Wizard 'Main-Loop', you probably should use an OS like FreeRTOS to give the SPI BSP an own task.