At least for the murmur/audio questions:
Try to note where they hear the murmur and where it radiates to. This can give you an idea as to the valve and type of murmur (regurg/stenosis) and help you narrow choices before you even listen to the murmur. FA has much of this...if you feel its lacking there is a nice set of tables/diagrams at the end of the murmurs chapter in Lilly.
When you listen to the murmur...try to pick up diastole vs systole. Diastole will be the longer time interval between S1 and S2 so use that to get your bearings of what is S1 and S2. Then try to identify the murmur as diastole or systole.
Finally go for the kill by matching the murmur to the diagrams given in FA. For this I recommend listening to murmurs and listening to the patterns (e.g. decrescendo, cres+decrescendo).
Lilly has good explanations of mechanisms if you are still struggling.