I've been running into trouble in both the alpha and beta versions of Mark IV when trying to work with the fonts script:
$ mtxrun --script fonts --list MTXrun | font table: accessing the data table failed MTXrun | font table: accessing the data table failed ...text/tex/texmf-context/tex/context/base/font-syn.lua:333: attempt to index field 'data' (a nil value)
Also, using the "reload" option does nothing (it prints a blank line and immediately exits). Without the fonts script I can't install or use any custom fonts.
I'm experiencing the same problem here. context version: 2009.04.18 13:47 LuaTeX, Version snapshot-0.39.0-2009042009 luatex.web >= v2329 None of my custom fonts work; I get errors define font | font with name texgyretermesregular is not found define font | unknown font texgyretermesregular, loading aborted define font | unable to define texgyretermesregular as \**dummy** define font | font with name texgyretermesregular is not found define font | unknown font texgyretermesregular, loading aborted define font | unable to define texgyretermesregular as \**dummy** define font | font with name texgyretermesregular is not found define font | unknown font texgyretermesregular, loading aborted define font | unable to define texgyretermesregular as \**dummy** define font | font with name texgyretermesregular is not found define font | unknown font texgyretermesregular, loading aborted define font | unable to define texgyretermesregular as \**dummy** Thomas