position of footer

[Dr. med. Kai Lautenschläger]

Dear list,

being on the list for only a few days has given me so many new ideas and input 
for improving my scores, that I like to send out my thanks for that first!!!

Now to my latest question: I tweaked the footers in my files with:

%% Einführung der Variable not-last-page
        #(define (not-last-page layout props arg)
                (if (and (chain-assoc-get 'page:is-bookpart-last-page props #f)
        (chain-assoc-get 'page:is-last-bookpart props #f))
        empty-stencil
        (interpret-markup layout props arg))) 
%% Einführung der Variable first-page
        #(define (first-page layout props arg)
                (if (= (chain-assoc-get 'page:page-number props 0) 1)
        (interpret-markup layout props arg)
        empty-stencil))

in the \paper block and 

oddHeaderMarkup = \markup \fill-line { \center-column { 
        \on-the-fly #first-page \rounded-box 
        \on-the-fly #first-page \pad-markup #0.3 
        \on-the-fly #first-page \fromproperty #'header:tonart } }
evenHeaderMarkup = \markup \fill-line { " " }   
oddFooterMarkup = \markup \fill-line { \center-column {
        %% Fuß alle Seiten außer erste und letzte
        \line { \on-the-fly #not-last-page \on-the-fly #not-first-page \vspace 
#2 \on-the-fly #not-last-page \on-the-fly #not-first-page  \override 
#'(span-factor . 2/3) \draw-hline }
        \line { \on-the-fly #not-last-page \on-the-fly #not-first-page  
\fromproperty #'header:hinweis  }
        \line { \on-the-fly #not-last-page \on-the-fly #not-first-page  
\fromproperty #'page:page-number-string }

        %% Fuß letzte Seite
        \line { \on-the-fly #last-page \vspace #2 \on-the-fly #last-page 
\override #'(span-factor . 2/3) \draw-hline }
        \line { \on-the-fly #last-page \fromproperty #'header:hinweis }
        \line { \on-the-fly #last-page \fromproperty #'header:tagline }
        \line { \on-the-fly #last-page \fromproperty #'page:page-number-string }
        }
}

in the \header with header:tonart and header:hinweis being defined variables 
elsewhere in the header-block

In the PDF the footer on the last page is positioned - as I know it -  close to 
the bottom of the paper. But the footers on the other pages ist positioned 
relative to the lowest system on that page. That usually makes it appear higher 
on the page, than on last pages. Does anyone have an idea, why that is this way 
and - even better - how I can fix it. Fixing means making the footer relative 
to the bottom of the paper on all pages. 

\version 2.15.39

Thanks so much.
best regards
Kai