[FusionHosting]

I believe I fixed the problem myself. I'm by no means a pro coder, but I did a search and discovered 2 of the functions you used in your code were older ones meant for the original GD library.

I changed 2 lines to refer to the GD2 libraries and now the .gif thumbnailing is working correctly for this particular image.

Here's the updated code:

switch ($imageExt){
                        case (".gif"):
                                        $srcImg = imagecreatefromgif("$imageDirectory/$imageName");
                                        $colortrans = imagecolortransparent($srcImg);
                                        $thumbImg = imagecreatetruecolor($width, $height);
                                        imagepalettecopy($thumbImg,$srcImg);
                                        imagefill($thumbImg,0,0,$colortrans);
                                        imagecolortransparent($thumbImg,$colortrans);
                                        imagecopyresampled($thumbImg,$srcImg,0,0,0,0,$width,$height,$imageWidth,$imageHeight);
                                        imagegif($thumbImg,"$thumbDirectory/$thumbName");
                                break;

imagecreatetruecolor, and imagecopyresampled were the two functions I swapped in.

Hope this helps anyone else with this issue.