i have experienced some "crashes" on mega while fixing my friends friends cpu, was downloading drivers on mega and was blocked out, at that time i was not looking for reason why mega was not working on chrome, but i have vague idea, that it is caused by antivirus, or missing Visual C++ Redistributable dll's, i fixed it by using different browser, like firefox. To claim that it crashes for you on all platforms, all browsers and different operating systems is big fat lie, there could be small chance that interet provider is blocking you out, but then again, if you dont live in north korea, why they would block some internet file storing cloud.