I had a similar problem and Nancy Folsom helped me solve it. Here is what I did.

In the Init of my form I have the following code:
THISFORM.pf.p_1.PageOrder = 1
THISFORM.pf.p_2.PageOrder = 2
THISFORM.pf.p_6.PageOrder = 3
THISFORM.pf.p_3.PageOrder = 4
THISFORM.pf.p_4.PageOrder = 5
THISFORM.pf.p_7.PageOrder = 6
THISFORM.pf.p_5.PageOrder = 7

Then inside each pageframe's PageOrder property I set each pageframe PageOrder property to:
PageOrder is 1 for the first tab
PageOrder is 2 for the second tab
PageOrder is 3 for the third tab and so on...

I can use the Init of the Form to change the pageframe tab order settings any time I want and they stay in the order that I set using this technique and don't get out of order. The reason I assigned them in a bizarre order in my Init was because I added some pageframe after I was all done with the form and needed them to fall in between some other pageframes. Hence, my appearance of out of sequence pageframes, but it is intentional in this case.

HTH

All the best,
Steve Kramer
http://members.aol.com/gocartoons