How to import Data Source Attributes with Calculations to existing Match Type in Oracle ARCS?

Is there a way to import changes to an existing Match Type in Oracle ARCS? I tried exporting existing Match Type, made changes to the 'MT_DSAttributes.csv' file and 'MT_Calculations.XML' file and tried Importing updated zip file. I get the following error message "An unknown error has occurred." and does not allow me to update with an Import file. The only components I was updated is to add additional Calculated Data Source Attributes that are used in another Match Type. I have at least 30 attributes to add and didn't want to add them manually if an import is available.