Hi,
This seems to work.
=========================================================================================================================================================================
\loadtypescriptfile[mathdesign]
\setupbodyfont[garamond]
\starttext
Some random text and \math{\alpha=\frac{-b}{2a}}
\stoptext
============================================================================================================================================================================
mtx-context | run 1: luatex --fmt="/home/fab/texlive/2013/texmf-var/luatex-cache/context/a86c089b384a3076dc514ba966a1fac9/formats/luatex/cont-en" --jobname="demo5" --lua="/home/fab/texlive/2013/texmf-var/luatex-cache/context/a86c089b384a3076dc514ba966a1fac9/formats/luatex/cont-en.lui" --no-parse-first-line --c:currentrun=1 --c:fulljobname="./demo5.tex" --c:input="./demo5.tex" --c:kindofrun=1 --c:maxnofruns=8 "cont-yes.mkiv"
This is LuaTeX, Version beta-0.76.0-2013061708 (rev 4627)
\write18 enabled.
(/home/fab/texlive/2013/texmf-dist/tex/context/base/cont-yes.mkiv
ConTeXt ver: 2013.05.28 00:36 MKIV current fmt: 2013.12.31 int: english/english
system > 'cont-new.mkiv' loaded
(/home/fab/texlive/2013/texmf-dist/tex/context/base/cont-new.mkiv)
system > files > jobname 'demo5', input './demo5', result 'demo5'
fonts > latin modern fonts are not preloaded
languages > language 'en' is active
(/home/fab/demo5.tex (/home/fab/texlive/2013/texmf-dist/tex/context/base/type-imp-mathdesign.mkiv)
fonts > typescripts > unknown library 'loc'
{/home/fab/texlive/2013/texmf-dist/fonts/map/dvips/mathdesign/mdugm.map}{/home/fab/texlive/2013/texmf-dist/fonts/map/pdftex/context/mkiv-base.map}
fonts > virtual math > the mapping is incomplete for 'mdugmrm' at 7pt
fonts > virtual math > the mapping is incomplete for 'mdugmbf' at 7pt
backend > xmp > using file '/home/fab/texlive/2013/texmf-dist/tex/context/base/lpdf-pdx.xml'
pages > flushing realpage 1, userpage 1
) )</home/fab/texmf/fonts/type1/urw/garamond/ugmr8a.pfb>{/home/fab/texlive/2013/texmf-dist/fonts/enc/dvips/ly1/texnansi.enc}</home/fab/texmf/fonts/type1/urw/garamond/ugmr8a.pfb></home/fab/texmf/fonts/type1/urw/garamond/ugmr8a.pfb></home/fab/texlive/2013/texmf-dist/fonts/type1/public/mathdesign/mdugm/md-gmr7y.pfb></home/fab/texlive/2013/texmf-dist/fonts/type1/public/mathdesign/mdugm/md-gmri7m.pfb></home/fab/texmf/fonts/type1/urw/garamond/ugmri8a.pfb>
mkiv lua stats > used config file: selfautoparent:/texmfcnf.lua;selfautoparent:/texmf-dist/web2c/texmfcnf.lua
mkiv lua stats > used cache path: readable+writable: '/home/fab/texlive/2013/texmf-var/luatex-cache/context/a86c089b384a3076dc514ba966a1fac9'
mkiv lua stats > resource resolver: loadtime 0.084 seconds, 2 scans with scantime 0.012 seconds, 125 shared scans, 59 found files, scanned paths: /home/fab/.texlive2013/texmf-config /home/fab/texmf
mkiv lua stats > stored bytecode data: 329 modules (0.170 sec), 69 tables (0.010 sec), 398 chunks (0.180 sec)
mkiv lua stats > cleaned up reserved nodes: 41 nodes, 9 lists of 441
mkiv lua stats > node memory usage: 2 glue, 2 penalty, 9 attribute, 28 glue_spec, 3 attribute_list
mkiv lua stats > node list callback tasks: 6 unique task lists, 6 instances (re)created, 40 calls
mkiv lua stats > used backend: pdf (backend for directly generating pdf output)
mkiv lua stats > loaded patterns: en::2, load time: 0.000
mkiv lua stats > jobdata time: 0.001 seconds saving, 0.000 seconds loading
mkiv lua stats > callbacks: 549 direct, 320 indirect, 869 total
mkiv lua stats > randomizer: resumed with value 0.77561070806142
mkiv lua stats > lxml preparation time: 0.000 seconds, 0 nodes, 15 lpath calls, 0 cached calls
mkiv lua stats > result saved in file: demo5.pdf, compresslevel 3, objectcompreslevel 3
mkiv lua stats > loaded fonts: 30 files: md-gmm7m.tfm, md-gmm7v.tfm, md-gmm7y.tfm, md-gmm8y.tfm, md-gmmi7m.tfm, md-gmmi8y.tfm, md-gmmma.tfm, md-gmmmb.tfm, md-gmr7m.tfm, md-gmr7v.tfm, md-gmr7y.tfm, md-gmr8y.tfm, md-gmri7m.tfm, md-gmri8y.tfm, md-gmrma.tfm, md-gmrmb.tfm, mdugmm7m.tfm, mdugmm7v.tfm, mdugmm7y.tfm, mdugmmi7m.tfm, mdugmmma.tfm, mdugmmmb.tfm, mdugmr7m.tfm, mdugmr7v.tfm, mdugmr7y.tfm, mdugmri7m.tfm, mdugmrma.tfm, mdugmrmb.tfm, ugmm8a.afm, ugmr8a.afm
mkiv lua stats > fonts load time: 0.185 seconds
mkiv lua stats > luatex banner: this is luatex, version beta-0.76.0-2013061708 (tex live 2013) (rev 4627)
mkiv lua stats > control sequences: 37496 of 65536 + 100000
mkiv lua stats > current memory usage: 73 MB (ctx: 73 MB)
mkiv lua stats > runtime: 0.539 seconds, 1 processed pages, 1 shipped pages, 1.855 pages/second
system | total runtime: 0.718
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Thank you.