Oh boy!
Wasn't really expecting this feedback for sure!
Will try to express it to the best of my abilities.

Anyway, with PPLandry (convenience wise) we did a Google Hangout while working it out on a Google Spreadsheet.
As you can see from this link, the project no longer has 14 tabs but only 2 now.
The second tab (monthview) can be obtained in a different way from the data one.
While in data tab, clicking on "data", then "filter" has many different options to choose from.
Seeing that i imported the working file into Microsoft Excel, i've discovered a few things and a few glitches to iron out.
PPLandry was kind enough to let me know that i can reach out to him again when needed.
So that is a huge plus.
Will try to iron out all the bugs before then.

A pastor was busy tidying up in his private room on the second floor of the rectory of small country parish one day...
The phone rang loudly in his office on the first floor (no cell phones or portable ones in those days).
Mrs. Ouimet, the native French speaking house cleaning lady quickly ran over to answer the phone.
"Allo!"
"May i have a word with Father Bob?" -asked the caller.
"Juste un instant, he's busy, he's up on top of me!" -she replied in her best English.

I'm open to suggestions Pierre.
This file is, however, the result of many hours of work with a friend who knows so much more about Excel than little ol' me.
That person has helped me in so many ways and when you find someone like that, it's not easy to go to someone else who might help you today and be gone tomorrow.