What version are you using?
I am using minimal not TeXlive2010. Of course, there are some bugs in beta. But it would be fixed soon.
Moreover, you can have more than one Minimal folder. So it is easy to use stable version if the beta has bugs.
BTW, where did you read to use front part instead of frontmatter?
There was a thread whose title is "Roman Page numbers".
And among the mails on 2009. 2. 4, there was a sample written by Wolfgang .
\definestructureconversionset[frontpart:pagenumber][][romannumerals]
\definestructureconversionset[bodypart:pagenumber] [][numbers]
\setuplist[chapter][pageconversionset=pagenumber]
\startstructureblockenvironment[frontpart]
\setupuserpagenumber[numberconversion=romannumerals]
\setuppagenumber[number=1]
\stopstructureblockenvironment
\startstructureblockenvironment[bodypart]
\setuppagenumber[number=1]
\stopstructureblockenvironment
\starttext
\startfrontmatter
\completecontent[criterium=all]
\chapter{Intro}
\input tufte
\stopfrontmatter
\startbodymatter
\chapter{knuth}
\input knuth
\stopbodymatter
\stoptext
Mailing list is a good place for me to learn ConTeXt. There are so many things which are not described in the manual.
I cannot give you a solution. But many experts who are reading this list will give you a solution.