Error with plugin after upgrade to VPS hosting

Wordpress drawing plugin was working as intended before hosting account was upgraded from a pro hosting account to VPS on inMotionhosting.com. The plugin is supposed to capture images on the page, create a thumbnail, then onclick paint over the html 5 canvas with that image. The before image included shows the thumbnail as it should appear. It's missing in the after image. Debugging error shown in the last image. Relevant code from the plugin: //From [login to view URL] function drawblogDoGetImgData(imgsrc){ var image_choices = [login to view URL]("drawblog_image_choices"); [login to view URL]({url:"<?php echo plugins_url();?>/drawblog/[login to view URL]", type:"post", data:"wpdir=<?php echo content_url();?>&imgsrc="+imgsrc, success:function(data){ img_data = [login to view URL](data); var newImage = [login to view URL]("IMG"); var tn_ratio = (50/img_data[2]); [login to view URL] = img_data[0]; [login to view URL] = 50; [login to view URL] = [login to view URL](img_data[1] * tn_ratio); var newwidth; var newheight; var hratio = wratio = 1; if (img_data[1] > <?php echo $width;?>){ newwidth = <?php echo $width;?>; wratio = <?php echo $width;?>/img_data[1]; } else newwidth = img_data[1]; if (img_data[2] > <?php echo $height;?>){ newheight = <?php echo $height;?>; hratio = <?php echo $height;?>/img_data[2]; } else newheight = img_data[2]; if (hratio > wratio){ newheight = img_data[2] * wratio; } else if (wratio > hratio){ newwidth = img_data[1] * hratio; } [login to view URL] = function() { drawblogPasteImg([login to view URL], newwidth, newheight); }; [login to view URL] = "pointer"; [login to view URL] = "1px solid #000000"; [login to view URL](newImage); } }); } //From [login to view URL] <?php $img = $_POST['imgsrc']; $wpdir = $_POST['wpdir']; $domain_bits = parse_url($img); $domain = $domain_bits['host']; $filename = $domain_bits['path']; if ($domain == $_SERVER['SERVER_NAME']) { $file = $img; } else { $file = $wpdir.'/plugins/drawblog/[login to view URL]'.urlencode($img); } $img_info = getimagesize($img); if ($img_info !== false){ echo json_encode(array($file,$img_info[0], $img_info[1])); } else echo ''; //From [login to view URL] <?php $img = urldecode($_GET['img']); $img_info = getimagesize($img); if (($img_info !== false) && (in_array($img_info[2], array(IMAGETYPE_JPG, IMAGETYPE_JPEG, IMAGETYPE_JPEG2000, IMAGETYPE_PNG, IMAGETYPE_GIF)))){ header("Content-type: ".$img_info[2]); readfile($img); }