Hi Stefan,
I am not seeing any other thing wrong in the debug log,Please try the below once,
1.Delete(or move somewhere if required) the existing output file,infolog and debug log of the device.
2.Try sending one command at once while configuring the activity (eg:first time send show version alone, on next run change the command as show interface extensive).
3.Then try more than one commands in single run.
4.No need to add any wait time in commands list.
5.And once these done, post me back all the three files with the results.
Thanks,
Nanda