Hi,
The data looks like this:
{"es-fields-22":"test","es-fields-24":"test","group_type":"1","es-fields-27":"","photo_albums":"1","es-fields-29":"1","es-fields-30":"1","es-fields-33":"{\"data\":\"\",\"position\":\"\"}"}
It varies depending on the field that the group have, and also depending on the field id of the field in the group.
While some field follows the key of "es-field-{id}", some uses a direct key such as "photo_albums".'
Unfortunately we can't actually list out all of the different keys and values for each individual fields but what you can do is go to the file /components/com_easysocial/controllers/groups.php and at around line 307 (may vary a little), search for the code $stepSession->delete(); and comment it out. Then try creating a group manually. This way the data will be intact in the database and you will be able to refer to the data format.