Thanks for your question. You can use the Bulk Edit area of the Media/Assistant submenu screen to assign Att. Tag values (or ALT Text values) at one time. Select the items you want by checking the boxes to the left of the thumbnails, select “Edit” from the Bulk Actions dropdown control and click “Apply”. The Bulk Edit area will open up and you can enter your value(s) there. Click “Update” to apply the changes.
You can also make assignments as you upload new items. Use the Media/Add New (Upload New Media) admin submenu. Click the “Open Bulk Edit Area” button before you add your items and enter the value(s) you want. Then, drag & drop or select the items you want to upload as usual.
I hope that gives you the information you need to accomplish your goal. I am marking this topic resolved, but please update it if you have problems or further questions regarding the above suggestions. Thanks for your interest in the plugin.