It looks to me like you may have introduced stresses to your plywood perhaps through your construction and bending techniques. If possible I'd try to let it all loose and try to rebend without forcing the plywood to go in a way it doesn't want to go. It's really hard to tell even from the pictures. Another possibility is that the inner cores of the plywood are not bending in conformity with the outer plies...thereby causing stess. Are the dimples paralleling or in conjunction with the direction of different areas of grain? What kind and thickness of plywood is it? Some plywood is just a bear to bend. Even though some sheets may look good, quality control is often lacking.