24168

Key 1 I made all the possible combinations to make 8 using dice.
I turned them over and they all added up to 13.
Key 2 I did it by trial and error starting on the left.
I got a lucky guess but checked for any other possible solutions anyway. The key was 9.
Key 3 I drew the circles and I knew that the diameter of each was 5cm and 1 cm was overlapping so the distance between the two centres was 4cm. So the key was 15.
Key 4 I figured out all the possible combinations. Then i had a play around with the numbers until it fitted. The sum of the corners was 24 so subtracting 10 gave 14.
Key 5 Because the trays could each fit 14 the total was 28. I counted by 4's and added three to all the numbers between 14 and 28. Then I did the same with the three times table but added 1 instead of 3. Then I found that within those numbers there were two 19's.
Then i used the 5 keys and converted them to letters and found my own name!