While you don't need to set this property (since templates are saved in your form, so once you chave loaded them you could safely delete them), it is normally very useful to have it set. If you set it, every time you modify the templates you can just right click the TemplateStore and press Refresh. 

In this property FlexCel stores the path for refreshing the template store. If RefreshPath is empty and you right-click the XLSTemplateStore on Refresh, FlexCel will ask for a folder and store it here. The next time, FlexCel will automatically refresh the store without asking. 

TXlsTemplateStore Properties