CR is working as designed, an aggregate is for a group, not a page.

you can accomplish what you are after using shared variables and a string...at least that is what I would do.

in the page header, I would reset the string to "" and the counter to 0 (I would also do this in a group header). Then in the detail section, I would have a formula that would check if the value is in the string, if not, increment the counter and add the value to the string. If it is in the string, do nothing.

now in the page footer, display the count.

hopefully your groups are forcing a new page before otherwise the count will be odd, and I will leave that case logic to you.

HTH

sorry, what you want to do, is not really possible in CR.
Why?
CR only reads 1 row at a time, and the aggregates are for the entire group. so you cannot suppress the column on page 2 and display if for page 3 for the same group.

a work around would be to use a subreport (which will slow the report down) or to use a stored proc, figure out a number protocol so that you can determine for any given group on a page if it will have to display the column (may not be doable, unless each group starts on a new page)

at least those are my ideas