More experiments, I am not one to be so easily defeated by software.
Retrieved some old beta's, each time I start a context run then it results in the loadfilemarkerror.
But I can find several formats lying around:
/Users/hans/TeX/ConTeXt/beta/tex/texmf-cache/luatex-cache/context/c180539b697aa06758debbc1182817e4/formats/cont-en.fmt
/Users/hans/TeX/ConTeXt/beta/tex/texmf-cache/luatex-cache/context/c180539b697aa06758debbc1182817e4/formats/cont-nl.fmt
/Users/hans/TeX/ConTeXt/beta/tex/texmf-osx-64/web2c/pdftex/cont-en.fmt
/Users/hans/TeX/ConTeXt/beta/tex/texmf-osx-64/web2c/pdftex/cont-nl.fmt
/Users/hans/TeX/ConTeXt/beta/tex/texmf-osx-64/web2c/xetex/cont-en.fmt
/Users/hans/TeX/ConTeXt/beta/tex/texmf-osx-64/web2c/xetex/cont-nl.fmt
Apparently none of them found! Vide this first message:
MTXrun | warning: no format found, forcing remake (commandline driven)

Here for inspection my .bashrc settings relevant to TeX. Could there be something amiss with these?
# TeX
export TEXLIVE=/usr/local/texlive/2010
export TEXPRIVATE=$HOME/TeX/My-TeXLib
export TEXMINIMAL=$HOME/TeX/ConTeXt/beta
export TEXPATH=$TEXMINIMAL/tex/texmf-osx-64/bin
export TEXMFDBS=$TEXMINIMAL
#$TEXMINIMAL/tex/setuptex
export TEXMF=$TEXMINIMAL
Note: inserting the hashed out line doesn't make a difference.

I append here the full terminal output below, just in case.