This event is all about the upgrade material and modifiers. You do not get points for upgrading your cubes despite it being called Cube Upgrade.
|Get 3 star Cube||20,000|
|Get 4 star Cube||100,000|
|Get 5 star Cube||500,000|
|Get 1 star Cube Enhance Material||100|
|Get 2 star Cube Enhance Material||500|
|Get 3 star Cube Enhance Material||2,000|
|Get 4 star Cube Enhance Material||5,000|
|Get 5 star Cube Enhance Material||20,000|
|Get Cube Promoter II||5,000|
|Get Cube Promoter||1,000|
Some daily quests can award you cube promotion materials
You can find Cube Promoters, and Enhancement Materials in the Reservoir War/Alliance Clash Exchange Shop for Clean Water.
You can also get it from some events like Trials of Survival.
Unfortunately, the best method is to buy Cube packages from the Mall.
I have found that once you have purchased the Cubes, you will be able to use all the Materials you have earned. However, again for this particular event, upgrading your Cubes does not give points only getting the Upgrade and Enhance materials.