If you select the Path Dresden Hbf Gleis 13 in the Scenario Planner, this Train will use the wrong side of the Track uphill from Tharandt. This Train will run on the wrong side at least as far as Klingenberg-Colmnitz. It can happen that this Train and a downhill Train block each other.
It isn't just DCZ that has this issue There is a DRA path from Riesa to Dresden via the slow lines through Coswig that runs on the wrong line from Niederau to Priestewitz which is quite annoying but needs fixed DTG JD or DTG Alex, can you pass this on for further analysis please and hopefully this will get fixed in the future EDIT: Realised it was the other way around so it is coming from Riesa to Dresden