I have been having some problems with my Plant3D equipment that has vent nozzles. After I place a smart vent nozzle the data somehow gets corrupted. The gooseneck nozzle will disappear sometimes after the dwg is closed, the other nozzles become un-editable, and the file looses the ability to add additional nozzles. I have restored previous versions and deleted the vent nozzle and everything seems to be fine. In the future I plan on using dumb 3D solids for gooseneck vent nozzles since nothing is connecting to them. Has anyone had a similar issue with vent nozzles?