Cover Oregon executive director Rocky King, left, is joined by Cover Oregon chief information officer Aaron Karjala at a Joint Interim Committee on Legislative Audits, Information Management and Technology hearing in Salem, Ore., Wednesday, Nov. 20, 2013. (AP Photo/Don Ryan)

Cover Oregon CIO Aaron Karjala resigns

Cover Oregon’s chief information officer, who worked to fix Oregon’s botched health insurance exchange since May, has resigned — the fourth …