The statistics module is only relevant for registered competitions scores submitted via the app or scorecard scanning.
This means you need to a be valid member of the club. If the link to MiStats is greyed out, this means that you are not logged in to that club or are not a member of that club.
The scores are relevant to a course and tee block to provide reasonable statistics. If you are a member at more than one club then the miStats will be specific for each club.
You can edit the round additional stats like putts and sand shots from either the app MiStats link to via your clubs website / desktop access.
Social scoring statistics is being looked at for a possible support in the later stage of the year.
Below image is a sample of the stats interface of MiStats which you can edit to include additional data like putts via your clubs member portal.