Unable to open RT file generated by Slicer

I loaded two nrrd volumes, one has the CT volume , the other has a binary segmentation mask. I am able to load and view them without any problem.
But when I try to save it by exporting to RTseries, it generates the dicom files for each slice and a single RTS dicom file. But when I try to load this directory it tries to load each slice as individual files along with the RTS like in the below screenshot

When I hit OK it loads all the slices as individual slices (is there any way it can be loaded as a single volume ?) but it gives a big error when it tries to load the rts file
vtkITKArchetypeImageSeriesReader::ExecuteInformation: Cannot open C:/Users/gabri/Desktop/2/rtss_1.2.826.0.1.3680043. ITK exception info: error in unknown: Could not create IO object for reading file C:/Users/gabri/Desktop/2/rtss_1.2.826.0.1.3680043.
Tried to create one of the following:
GiplImageIO …

Some images may be loaded using “Add data” window, but in generatl you need to open DICOM files using DICOM module.

I would recommend to use the latest Slicer Preview Release, as it has many DICOM support improvements.