After creating any personnel tile, click the Hamburger menu in the header of that personnel tile, and select "Arrange Tile Content".
In the Tile Content Editor, to add custom stats, FIRST click the "Add Stat Folder", THEN clicking to delete the auto-generating stat row. The custom stat-box will not generate if you do not follow this order.
After adding the custom stat box, re-arrange the tiles and re-size to make the stat box fit, then click the "X" in the top left to exit the Tile Content Editor.
To edit stats, click into any of the spaces and type the stats in.