Alot of it is to do with how the paint is stored before the tourney and during the tourney!!
For instance if the paint was not stored properly ie the boxes of paint turned to stop dimpling and kept at the correct temperature then your on a hiding to nothing already !!
If the paint was stored after it was bought at the store and put on the cold garage floor it will make the paint brittle and your again in deep doo do!!
At the tourney if it has been stored correctly and is then left iin the cold air in between games it will become brittle and soup city here we come!!!
Suggestions:-
Well buy your paint from a reputable dealer in other words they store it correctly
Store it at home inside the house at room temperture when at the tourney take out only the paint that you need keep the rest in the car with the heaters on,any unused paint after each game take it out of the pots and put it back in the car to warm up again and use the warmer paint that has been kept in the car.
Use a bigger bored barrel to compensate for the paint being brittle less drag on the ball as it is being shot down the barrel , use a known harder ball you might get more bounces off players but at least you aint cleaning your marker every third shot.
Finally if you are lucky and have someone in your team clever enough to convert a small refrigerater to actually warm up instead of cool down and run it from a generator you will have nice warm balls all the time
!!! You may get some strange looks at first but then they will all wont a ball warmer when you shooting them out with a not so hard paint just rotate your pot after each game!!
Hope this helps after years of playing in the British winter it some of the tricks of the trade we've used in the past