The GAM does not seem to work for adding additional sizes to existing shear studs. For example: I want to add an additional length to the shear stud listed as Nelson H4L inch. There are multiple lengths for the 1/2" diameter. However 3" is not one of the options. I add a new one by entering all the relevent info into the length, weight and part name columns and click on the Apply button and everything disappears and nothing is saved. What am I doing wrong?