INDD CS 5.5 --- add a page and the entire gets wrecked?

First of all, I have found these buttons to be VERY helpful regarding what I am about to say:

http://www.ccwatershed.org/media/photologue/photos/001_Helpful.jpg

Anybody else love those??  OK, here goes:

1.

OK, so I used to make files that look like this:

http://www.ccwatershed.org/media/photologue/photos/002_Origialna.jpg

. . . and they looked fairly decent:

http://www.ccwatershed.org/media/photologue/photos/003_looks_nice.jpg

2.

But there was an AWFUL PROBLEM.  Every time I would add a page:

http://www.ccwatershed.org/media/photologue/photos/004_add_page.jpg

. . . the entire file (ALL the pages coming after the added page) would become totally screwed up, like so:

http://www.ccwatershed.org/media/photologue/photos/005_Messed_up.jpg

3.

So, now I am trying to do something that looks like this:

http://www.ccwatershed.org/media/photologue/photos/006_new_attempt.jpg

4.

It seems to be working OK, because when I add a page:

http://www.ccwatershed.org/media/photologue/photos/007_add_page.jpg

. . . it appears NOT to wreck everything:

http://www.ccwatershed.org/media/photologue/photos/008_fixed.jpg

OK, SO HERE ARE MY THREE QUESTIONS:

Question A:

Is this the correct way to do it?  Does everybody already know this?  How come it took me almost 5 years to learn this?

Question B:

What is the best way to "line up" the center thing?

http://www.ccwatershed.org/media/photologue/photos/009_Line_up.jpg

Question C:

I used to have issues where, after adding a page, INDD would totally screw up my file like this:

http://www.ccwatershed.org/media/photologue/photos/010_NO_MORE.jpg

But that doesn't happen to me anymore: why?