Version 2.1 Update
Aha... a bug! I forgot to put the TEMP cache directory variable in the right place - instead, I hard coded it by mistake!

Thanks BigCheeze for letting me know.
I've updated the FTP.PHP file in the ZIP file to version 2.1 - just download and upload the new version.
Or, to upgrade from vB FTP 2.0 to 2.1, just do this:
In ftp.php, find:
PHP Code:
$open = opendir("./tmp/");
while (($file = readdir($open)) != false)
if (is_file("./tmp/$file")) @unlink("./tmp/$file");
Replace with:
PHP Code:
$open = opendir("$temp_dir");
while (($file = readdir($open)) != false)
if (is_file("$temp_dir/$file")) @unlink("$temp_dir/$file");
ie. - replacing the hardcoded "tmp" directory with the $temp_dir variable. The image viewing will not produce any errors.
Thanks!