Colors Deleting with Deselection

[#1]

I made a rather complex image of a moutain viewed from afar, and, to create a proper paralaxing effect, I need to expand the image I drew lengthwise. The problem is that when I have expanded it to the desired length and proceed to deselect the layer, large swaths of specific colors disappear.

What I have tried:

Converting to symbol & movie clip

Replacing true white with a light blue

Selecting other layers instead of hitting the deselect shortcut

Original MountainMountain expanded and subsequently deselected

[#2]

I've had this same problem myself quite frequently when making very complex vector art. Usually I'm able to skirt around it by grouping the drawing or converting it to a symbol before resizing, but it sounds like you've already tried that with no success.

My only other suggestion would be to go to Modify>Shape>Optimize and set the strength as high as you can without compromising your artwork. I've had that solve the problem in the past.

Good luck!