TwinCAT Run Configuration XMC4800

Hi,

I followed the example of Infineon on how to setup the XMC4800 as a EtherCAT Slave.
In TwinCAT I configured one special CPU just for TwinCAT to make the application Realtime-capable.
In the Config Mode of TwinCAT everything is running nicely, but when I try to activate the Run Mode the Slave cannot be set to OP. Instead it is in PREOP.
How do I need to configure TwinCAT to make the simple example work in Run Mode?

Thanks in advance,
Lukas