And why exactly do you think you need a column to hold the total? Just calculate it with MySQL when needed:
r1 + r2 + r3 + r4 + r5 AS total -- this is bad design
However, the poor database design already shows in this simple query: When you have a group of values, you do not create a column for each one. This violates the First Normal Form. A dead giveaway for this problem is that you start numbering your columns.
Instead, you create an extra table to store the values as rows. In your case, you'd have something like this:
ref_id | round | points
2 | 1 | 90.0
2 | 2 | 412.0
The huge advantage is that doing calculations accross the rows becomes trivial, and you can change the number of rounds at any time.
Now the query is as simple as this:
, SUM(points) AS total