Header background won't go away

[Duncan Hothersall <dh@capdm.com>]

Hi all.

I have a book with parts and chapters, which wants a tint in the 
background of the header line. I have the following set-up producing 
almost what I want (apologies for the length but I've stripped out as 
much as I can to still show the same effect):

--
\setupsectionblock[bodypart][page=right]
%...
\setuppagenumbering[alternative=doublesided]
\setuplayout[location=doublesided,
         backspace=8.5pc,topspace=5.5pc,top=0pt,topdistance=0pt,
         header=12pt,headerdistance=12pt,height=61pc,footer=16pt,
	bottom=6pc,leftedge=9pc,leftedgedistance=0pt,leftmargin=0pt,
	leftmargindistance=0pt,width=29pc,rightmargindistance=0pt,
	rightmargin=6.5pc,rightedgedistance=0pt,rightedge=6.5pc]
\setuphead[part]
      [placehead=yes,command=\XPart,resetnumber=no,page=right,
       header=high,before=,after=]
\def\XPart#1#2{#1 #2} %simplified
\setuphead[chapter]
      [command=\XChapter,header=high,
       before=\vbox to 14pc\bgroup,after=\vss\egroup]
\def\XChapter#1#2{#1 #2} %simplified
%...
\setupcolors[rgb=no,cmyk=no,spot=yes,state=start]
\definecolor[PantoneTwoNineFour][c=1,m=.56,y=0,k=.18]
\definecolor[IFSblueheadertint][PantoneTwoNineFour][p=.12]
%...
\setupbackgrounds[header]
      [leftedge,leftmargin,text,rightmargin,rightedge]
      [background=color,backgroundcolor=IFSblueheadertint,state=start]
\setupheader[state=start]
\setupheadertexts[margin]
	[]
	[\hfill\llap{\tfx\getmarking[chapter][current]}]
	[\hbox to \leftmarginwidth{\rlap{\tfx\getmarking[section][last]\hfil}}]
	[]
%...
\starttext
\startbodymatter
\part{First part}
Looks good, but still has band on next page
\chapter{First chapter}
Looks good, no band on first page of chapter. \page[yes]
\section{First section}
Looks good, the band is there. \page[yes]
\section{Second section}
Looks good, the band is still there.
\chapter{Second chapter}
Ugh, the band has impinged on my title, and I'm getting an extra odd 
page at the end too.
\stopbodymatter
\stoptext
--

The above code runs in live.contextgarden.net and demonstrates my 
problems, which are:

1. The big problem - the second chapter title page doesn't suppress the 
band, even though the first one did. NB this behaviour seems to change 
depending on whether the previous chapter ends on an odd or even page. 
Bug, or incorrect header setup?

2. Empty pages (like the back of the part title) have the colour band on 
them - how can this be suppressed for empty pages?

3. There's an extra odd page at the end (I've tried a few of the 
suggested fixes for this but can't get them to work).

If anyone can answer, especially question 1, I'd be really grateful!

Thanks,

Duncan
dh@capdm.com