Short answers, pulled from the story.
British intelligence estimated Axis strength at 35,000 men while the true figure was about 80,000. This miscalculation left the Eighth Army unprepared for the scale of the coming offensive.
In the early hours of the 27th of May, Rommel led elements of the DAK and XX Motorised Corps in a bold flanking move using Allied minefields for protection. The Ariete Division was held up for about an hour by the 3rd Indian Motor Brigade at Rugbet el Atasc.
The garrison of 33,000 men was captured many having not been engaged on the western perimeter. Over 1,000 vehicles in working order plus food and petrol were captured.
Hitler rewarded Rommel with promotion to field-marshal making him the youngest German officer ever to achieve this rank. Rommel remarked he would have preferred another panzer division instead.
Black Saturday became known as the date when the Eighth Army suffered devastating losses. On the 13th of June, the 21st Panzer Division advanced against the 22nd Armoured Brigade at Knightsbridge and overran part of the 2nd Scots Guards at Rigel Ridge.