Hi markus,
We actually fixed that bug in the 8.5 version of the CVI RTE which you can download here. I would rather you not try and downgrade the RTE since its much easier for us to help you out if you use the latest version. We state that the CVI RTE provides backwards compatiblity and we stand by that claim so any problems you have, we will address.
Let me know if this doesn't work for you.
Best Regards,
Jonathan N.
National Instruments