Among Germany's seemingly innumerable young topnotch abstract painters, Hellmich has a franchise in architecture-derived complexities of zippy hard edges, delicately distressed surfaces, and day-dreamily sweet and acrid colors. The pictures' off-kilter rumpuses make you want to comprehend them. Fat chance. Negotiating Hellmich's decisive disorder is like clambering around a construction site in an earthquake. Through Feb. 20 (Lehmann Maupin, 540 W. 26th St. 212-255-2923.)