conditional and one more

Hi,

1. Is this conditional? No. 2 Conditional, perhaps? What troubles me is I think I saw all these variations in the if--clause. Is this possible?

I would appreciate it if you can call/would calll/could call/call this person as soon as possible.

2. Is this structure possible?

It's a little bit of maze.

I gather 'maze' is a noun and functions as a noun here.

3. I think you can say. "I find you sincere." By that, I assume the person meant to say "I think you are sincere."
Can it work for the past tense version? Which one is good?

I found you sincere yesterday. Or, I found you to be sincere yesterday.