Open the XMIM or MIMIC application and use the symbol browser to verify that the symbols and categories were created.
For example:
Open the XMIM application.
Select the Search Database
button. Select the new categories (Other>WidgetsInc>WID_Forwards>WID_Electricity) until you see the new symbols: WID.NYISOE.OFFPEAK and WID.NYISOE.ONPEAK.