Thank you for your interest, Aditya. The error was kindly fixed by Hans introducing the following fix at line 993 in tex/texmf-context/tex/context/base/mkxl/back-exp-imp-mth.lmt: function extras.msubsup(di,element,n,fulltag) local data = di.data local nuc = found(data) local sup = found(data,"sup") local sub = found(data,"sub") data[1] = nuc or dummy_nucleus data[2] = sub or dummy_nucleus data[3] = sup or dummy_nucleus data.__i__ = 3 local sp = specifications[di.fulltag] if attributes then attributes.mathsupindex = sp.supshifted attributes.mathsubindex = sp.subshifted else di.attributes = { mathsupindex = sp.supshifted, mathsubindex = sp.subshifted, } end end This solved the issue. -- Andrés Conrado Montoya Andi Kú andresconrado@gmail.com http://sesentaycuatro.com http://messier87.com http://chiquitico.org ---------------------------------------- Los fines no justifican los medios, porque la medida verdadera de nuestro carácter está dada por los medios que estamos dispuestos a utilizar, no por los fines que proclamamos. ---------------------------------------- “You develop an instant global consciousness, a people orientation, an intense dissatisfaction with the state of the world, and a compulsion to do something about it. From out there on the moon, international politics look so petty. You want to grab a politician by the scruff of the neck and drag him a quarter of a million miles out and say, ‘Look at that, you son of a bitch.’” — Apollo 14 astronaut Edgar Mitchell