Errors with demo software

Apologies if this is obvious but I am a newbie to ARM and am struggling.

If I load STM32F429-Discovery EmWin example it compiles Ok.

Change the device from STM32F429ZIT to STM32F429IGT (on my board) I get errors:

compiling RTX_Conf_CM.c...
compiling SPI_STM32F4xx.c...
C:\Keil_v5\ARM\PACK\Keil\STM32F4xx_DFP\2.2.0\CMSIS\Driver\SPI_STM32F4xx.c(600): warning: #177-D: function "SPIX_GetVersion" was declared but never referenced static ARM_DRIVER_VERSION SPIX_GetVersion (void) {
C:\Keil_v5\ARM\PACK\Keil\STM32F4xx_DFP\2.2.0\CMSIS\Driver\SPI_STM32F4xx.c(610): warning: #177-D: function "SPIX_GetCapabilities" was declared but never referenced static ARM_SPI_CAPABILITIES SPIX_GetCapabilities (void) {
C:\Keil_v5\ARM\PACK\Keil\STM32F4xx_DFP\2.2.0\CMSIS\Driver\SPI_STM32F4xx.c(622): warning: #177-D: function "SPI_Initialize" was declared but never referenced

etc.

If I now change back to original device I still get these errors. Why?