As reported by Sascha, the batch upload (multiple images upload) in administration return problems and do not work as needed. While the single upload has been fixed in the new w3images 1.1.3, the batch upload will be fixed within the w3images 1.1.4, released in some hour more.
The batch upload bug has been fixed as scheduled yesterday:
the w3images archive will be updated with the fixed images-options.php file that resolve the ‘batch upload issue’.
The w3images will be released as version 1.1.4 in very short time (few hours), and to update from 1.1.3, it is only needed to overwrite the images-options.php file contained in wp-content/plugins/w3images/ folder with the fixed of the w3images 1.1.4 archive.
Thank again to Sascha for his bugs report.