The code below did work ok some version of ConTeXt ago, now an error and I cannot think of the cause.

There is an unknown file ./t. Is it origin something with the jobname mysteriously being t? Or is it perhaps that modules now have names preceded by t- ? I am completely baffled.
Help would be very much appreciated because I have not much time left to finish the text.

Macro for calling a context run:

% Call context for figures #1 = mode, #2 = fontchoice, #3 = colorchoice, #4 = file without .tex extension.
\def\callcontext[#1][#2][#3]#4{%
\writestatus{HVDM}{CALLING DIRECTLUA file=#4 mode=#1 fontchoice=#2}%
\directlua{os.execute("cd \FigSrc;context --once --mode=#1 --font=#2 --colors=#3 --purge #4;rm #4.tuc;cd -;mv \FigSrc/#4.pdf \FigDir")}%
}

HVDM            > CALLING DIRECTLUA file=taalengels mode=screen,info fontchoice=lucidaot,sans,12pt\tt

resolvers       | trees | analyzing '/Users/hansm/Documents/TeX/texmf'
mtx-context     | warning: no (local) file './t', proceeding
mtx-context     | run 1: luatex --fmt="/Users/hansm/Applications/TeX/context-28/tex/texmf-cache/luatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/formats/luatex/cont-en" --jobname="t" --lua="/Users/hansm/Applications/TeX/context-28/tex/texmf-cache/luatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/formats/luatex/cont-en.lui" --no-parse-first-line --c:colors="darkslategray,darkslategray,mistyrose,darklavenderblush,peachpuff" --c:currentrun=1 --c:font="lucidaot,sans,12pt" --c:fulljobname="./t" --c:input="./t" --c:kindofrun=3 --c:maxnofruns=1 --c:mode="screen,info" --c:once --c:purge "cont-yes.mkiv"
This is LuaTeX, Version beta-0.80.0 (TeX Live 2015) (rev 5238)
 \write18 enabled.

resolvers       > trees > analyzing '/Users/hansm/Documents/TeX/texmf'

system          > callbacks > not registering frozen 'find_format_file'
open source     > 1 > 1 > /Users/hansm/Applications/TeX/context-28/tex/texmf-context/tex/context/base/cont-yes.mkiv

ConTeXt  ver: 2015.10.09 21:28 MKIV beta  fmt: 2015.10.11  int: english/english

system          > 'cont-new.mkiv' loaded
open source     > 2 > 2 > /Users/hansm/Applications/TeX/context-28/tex/texmf-context/tex/context/base/cont-new.mkiv
close source    > 2 > 2 > /Users/hansm/Applications/TeX/context-28/tex/texmf-context/tex/context/base/cont-new.mkiv
system          > files > jobname 't', input './t', result 't'
fonts           > latin modern fonts are not preloaded
languages       > language 'en' is active

tex error       > tex error on line 8 in file /Users/hansm/Applications/TeX/context-28/tex/texmf-context/tex/context/base/cont-yes.mkiv: ! I can't find file `./t'.


Hans van der Meer