SPOILER STORY 5. Loss of will secrecy and other Qs

By Lightster, in Mansions of Madness

First of all, the game (objective 1c) was really REALLY fun. But we got questions:

1) may the keeper reveal the objetive to the lose of will player?

2) there are some weapons that says "attack a MONSTER within X range". Does this mean that investigator can't attack each other with this weapons? if so, how can they attack each other? what are the rules? (ie, the monster is stunned, does the investigator becomes a monster for this purpose?)

3) reading the other objectives I found a little confusing 2b. the loss of will player can enter the room and then I win? what can I do (apart from playing mind tricks) to make them enter the freezer? is it neccesary to explore the room or just revealing the killer card wins the game?

thanks you guys!