Hi, I wanted to share some observations from enabling the latest MkIV  
code (2008.09.24, compiled luatex from svn just now) to run on a new  
installation of TeXLive 2008 on 64bit Linux.  This is my first time  
trying MkIV.

First -- a comment on installing using TeXLive 2008, which hopefully  
is helpful to others.  In my installation I noticed that  
x86-64/bin/luatools was symlinked to  
texmf-dist/scripts/context/stubs/unix/luatools.  The rsync update  
process as outlined on garden does not update this file; it updates  
texmf-dist/scripts/context/lua/luatools.lua.  So this needs to be  
copied (or linked) over to make the update work.  The same issues  
exists with mtxrun.  The symptom was a broken "context --make".

Now, on to my issues.  I am listing anything that used to work in my  
TeXLive 2007 installation of MkII but fails in 2008 (MkII or MkIV).   
Items 1-3 were tested on garden as well to ensure it was not an issue  
in my setup --

1. \placefloat[here]{none} fails.  \placegraphic works instead.  This  
works on MkII.  See test_placefloat.tex.

2. MkIV fails due to the \startcolor...\stopcolor sequence embedded in  
a natural table (see test_color.tex).  A working alternative is  
commented in that file.

3. MkIV will not typeset the file test.tex.  It is due to using  
{style=\switchtobodyfont[tt]} in the table setup.  Using [modern,tt]  
works fine, but this is not necessary with MkII.

4. This is a MkII issue (or maybe it is a pdftex problem?)  MkII on  
2007, texexec --dvi on 2008, and MkIV all work.  The problem is with  
pulling in an external figure like this --

\externalfigure[/tmp/testfigure]

The files /tmp/testfigure.eps and /tmp/testfigure.pdf exist.  This  
should use the full path to find the file, and will pick the eps when  
creating dvi and the pdf when creating pdf's.  As mentioned, this  
works with every combination I tested except 2008 MkII.  Some (not  
very usable for me) workarounds are --

- use the filename without the path and add the path using  
\setupexternalfigures[directory=]
- specify the .pdf extension (means I cannot typeset to dvi if I want  
to; I find this useful for previewing with xdvi's auto-reload)
- use \setupexternalfigures[directory=/] and use a relative path

5. Just a comment on performance -- I noticed that using MkIV on a  
complicated document I have took 23 minutes vs. 12 minutes with MkII.   
I didn't know if MkIV is expected to be slower/comparable/faster at  
this stage.

Anyway, I hope this is useful to other users and to the developers.

Best Regards,
Brian