Whatever he did to help Roth (which does remain an unanswered question), I don't think even Fredo would aid in anything that he thought would bring harm to Michael. Even a potential kidnapping, which has also been discussed it the past.

And just being Michael's brother wouldn't necessarily give him access to roam around the house and open the bedroom drapes.

The drapes thing is another of those 'holes' that just have to be accepted and forever open to speculation because there's just no concrete answer.

Another unresolveable problem with the whole drapes thing regardless of WHO opened them is:

Why would Kay Corleone, who has presumably lived in that house for at least 4 years, suddenly one evening after a huge party consisting of hundreds of guests, many of whom she did not know and some of whom probably remained as guests on the compound...get into bed and comfortably under the covers without noticing that her bedroom curtains were open until her husband was standing in front of them.

Know-it-all bitch that I am, I can tell you it's just not something a woman would do. Especially a woman who is presently unhappy and mistrustful with her current 'family' situation.

So as with many films that are otherwise great, there is a certain futility in micro-analyzing and trying to find an answer to many of the details which are really unanswerable or at best lead to another unanswerable question.

But I agree...it can sometimes be fun.

Apple