For contours nor displaying query, first, try exporting the contours to native format. This is done by right clicking the entry in the contour manager (View > Contours), then choosing to export to native format. If this does not help, please upgrade to the latest version of WaterCAD/GEMS and apply the latest corresponding cumulative patch set.
The directions for downloading latest version can be found in the following wiki:
Downloading OpenFlows | Hydraulics and Hydrology Software
How do I label my contours when using the AutoCAD platform?