Im on CS6 but I take is the same. This might have happened to you:
If you used gradient in the stroke, or tried to change the height and width of the regular radial gradient, to make the shading oval instead of a circle this won't convert to early version that didn't have this function.
Check your flower petals.
If you go on the Window>grandient> the flyout menu opens. Click on the tiny black arrow on the top right to open "show options". Click on RADIAL.
You see the angle input bellow...That's okay to use, but the width /height option bellow is not supported in earlier versions and hasn't converted for me.
You will have to redo the gradients, being careful not to "squish the gradient" in the oval shapes.