SAT Mission Time Mini-Sections not working properly

While doing the SAT mission questions, that are timed, the site breaks or freezes. It is difficult to scroll down the question if it is a Reading and Evidence-based writing timed mini section. It is not my internet problem for sure, because it is almost always, and the internet connectivity is not bad. 
As I start the timed mini section of Reading or Writing and Language part, it runs smoothly till I get to, I think, last four minutes. I am not able to click on answers properly or even read the question properly in the time, and I end up getting frustrated and not focusing, getting the answers wrong. Please fix this for me. I am a great fan of the timed-mini section for training, but it has this problem. I am not quite sure about Math's timed mini-section because 
1) We cannot scroll it, like in Reading or Writing questions.

2)  I finish all questions before i reach last 5 minutes, so I am not confident about math section.

We can go to next question, may be, by clicking, the next question option in Reading or Writing test, but scrolling is easy and helpful, so I prefer it. If the solution is clicking particular question buttons or next question option at bottom right, I would try it, but please fix the scrolling problem.