Hi,
We understand that the specific example was created for an M7 core, hence the following preprocessor symbol is added to the project:

This seems to define the startup procedure. Since, we understand, that the M7 core requires a different initialization routine than the A53 core, this creates a conflict.
As for the RTD, we see the following information is provided under the Release Notes:

For which, we understand that no examples are provided under the specific RTD version for the A53 core. If required, we can recommend starting with an easier example, like Siul2_Dio_Ip_Example_S32G399A_M7 (the blink example) for these situations and start modifying it, since there is no example available (nor debug configuration) for the A53 core and we understand that there is no documentation for this situation. We do apologize.
Please, let us know.