NEW YORK — He may have presented his collection via CD-ROM last season, but for fall, Helmut Lang showed the low tech way: on the runway. Lang delivered the urban basics his customer craves, but he also threw her a curve or two. Aran-style sweaters with offbeat twists and turns and others that resembled shag rugs, for example, were shown layered cozily under clean-cut coats. Here, his anorak, sweater and pants. For more, see pages 4 and 5.