Sponsorship Evaluation Question

I am a Canadian citizen sponsoring my spouse on an outland app. She is from Sweden. I have no dependents, she has 3 non accompanying dependents.
I'm a little confused and don't want to make a mistake on questions 5 & 6 on IMM 5481E and would appreciate any help in advance.
On question 5. A) would I write in "4" in the box?
I've had no previous undertakings so I put a "0" for each box in 5. B) ?
6. A) and 6. B) I put "0" in each box?
and of course I put a "5" in question #7 if I've been correct so far?

Also I am self employed as in question 2. C) and will fill out question #3 "your net personal income". I thought that I read something to the effect that if you are sponsoring your spouse you don't have to show your income?

And the last question that I hate to ask but need to know is: if one person used check marks to mark boxes and the other person used crosses(X) to mark their boxes, would this cause your app to be sent back?...or is this a silly question of checks and crosses?

I've read every post on this site in preparation to help myself with my app and wanted to try to answer everything as well as I can without asking any lame questions...but I do need some clarification.

Thank you and good luck to all

canswede