希望可以一起交流SAT语法问题,

希望可以一起交流SAT语法问题,
1.Even when Barbara Jordan put questions toward a political nominee,her elegant diction evoked in listeners memories of her eloquent political speeches.
答案说“toward”错了,是不是应该改为“to”呢?（question 后面的介词用to?) 怎么理解句中的“even when”呢?为什么不把“even”去掉呢?
2.Only by the afterglow of the sunset could the hikers find their path to the campsite at so late an hour.
可以把“could”改为“did”吗?“so late an hour”怎么理解呢?