There are no option in Stat to make "Tracking number" field required/mandatory field. There is an enhancement request open for this issue and it will be considered by Stat development department for future versions of Stat. You can also submit an enhancement request on your own behalf. To log an enhancement request for this feature, please visit the Stat Community Idea portal at http://communities.quest.com/community/stat?view=idea.
This area of the Stat community is dedicated to tracking customer enhancement requests and allowing the community to discuss usecases and vote on the most useful features for consideration in future releases. Once you get to this page mouse click on "Login" link on top. If you do not have a login mouse click on "Register" link on top and fill in the requested information.