I have known this to happen with older video cards that do not have programmable shader support. What video card do you have? If it is a modern card, I will have to research further.
Update:
Researched this further, and concluded that the card in question did not have Pixel Shader/Shader Model 2.0 support, which is required to run this game.
completed 10k coins in 1 run and went over 50k distance. Next challenge, do 50k distance - then suddenly I can't get within 5-10k of that distance ever again. If we do 50k or more for the 10k coin challenge we should automatically win.
being able to downgrade might be helpful too, so I can get the less than 100m achievement. And lose about 90% of those balloons or make them poppable because I don't think u understand how an air balloon really works.
I have known this to happen with older video cards that do not have programmable shader support. What video card do you have? If it is a modern card, I will have to research further. Update: Researched this further, and concluded that the card in question did not have Pixel Shader/Shader Model 2.0 support, which is required to run this game.