BOULDER — The loudest cheer from the student section came early during halftime when a Buffs fan wearing gold-and-black overalls and not much else came charging out of the undergraduate throng and onto Folsom Field. Skippy McOveralls ran untouched into the north end zone before security corralled him out of bounds. It was the closest anybody wearing CU colors got to breaking the plane all day. “Offensively, we’re struggling in a number of areas,” Buffs coach Karl Dorrell said after his era hit a new nadir Saturday in a 30-0 loss to Minnesota, the program’s first shutout home loss in nearly 10 years. “And it’s not just the quarterback.