You can playback a 6x6 spritesheet using a pure shader with uvmap, like this :
//control
float images=6; //6x6 spritesheet
float speed=10000;
float X=floor(images*(mod(currenttime/speed,1)));
float Y=ceil(images*(mod(currenttime/(speed*images),1)));
outcolor *= texture(texture0,vec2(ex_texcoords0.x/images+X/images,ex_texcoords0.y/images+Y/images));