Greetings, I'm using ConTeXt Standalone 2011.09.27 20:05. \usemodule[simpleslides][style=Shaded] \starttext \SlideTitle{The first slide} Hello, world. \SlideTitle{The second slide} Greetings, world. \stoptext ! Undefined control sequence. system > tex > error on line 5 in file slides.ctx: Undefined control sequence ... 1 \usemodule[simpleslides][style=Shaded] 2 \starttext 3 \SlideTitle{The first slide} 4 Hello, world. 5 >> \SlideTitle{The second slide} 6 Greetings, world. 7 \stoptext 8 <argument> \@@MPG \simpleslidescounter \executeifdefined #1->\ifcsname #1 \endcsname \csname #1\expandafter \expanda... \includeMPgraphic ...\executeifdefined {\@@MPG #1} ; <argument> ...udeMPgraphic {\simpleslidescounter } ; fi StopPage ; \processMPgraphic ...ntMPgraphicformat ", \!!bs #1 ;\!!es , \!!bs \currentMPi... \handleuseMPgraphic ...hics \processMPgraphic {#3} \endgroup ... l.5 \SlideTitle{The second slide} Changing the style to "Swoosh" throws a different error message ("Undefined x coordinate has been replaced by 0.", apparently by Metapost). Presentations consisting of a single slide are processed without errors; from my cursory glance at the code, the problem lies either with the setups or with the slide counter. Cheers, ~~ Ondra