Tools versions:
TESSY v4.2.8
TrueSTUDIO for STM32 9.0.1

Hardware:
Prozessor: STM32L031K6T6 (ARM Cortex-M0+)
Board: STM32L031 Nucleo-32
Interface: Micro USB B

Important hint:
All you need to set for this example project is
TEE attribute "TrueStudio Install Path", which
you will find in the project's compiler node at
the bottom of the attributes list.