Does the demo run on the EFM32 Board EFM32G290F128?
The Board has no LCD.
I have to use the external bus, or?
how do I implement this?

If the demo uses and LCD, and your board does not have an LCD, then it goes without saying that you will not be able to view anything on the LCD that is not there.  As far as the EMF32 port goes, it is ‘just’ a Cortex-M3, so the port will run on any Cortex-M3 from any manufacturer. Regards.

Yes, thank you.
But, If the software comes to the point “Performs USART2 SPI Transfer” -> “/* SPI address */” ->while (!(usart->STATUS & USART_STATUS_TXC)) ; nothing is happens.

To translate Richard’s reply. The Cortex-M3 port runs on any Cortex-M3 device, but there is a difference between a port and a demo. The demo just targets a port at a particular hardware platform or development board. If you are using a hardware platform other than that targeted by the demo you may have to make some changes to get the demo running. Normally this is restricted to changing the port pins used for LED outputs or button inputs. In your case, if there is no LCD, then remove any code that is trying to communicate with the LCD, especially if it is expecting the LCD to reply to commands.