I also upgraded to WordPress 4.4.1 and WP-Filebase Pro 3.3.3. My embedded form is located in the middle of my page, surrounded by instructions and explanatory text. When I try to upload a file using the Drop and Drag feature, a second Drop and Drag/embedded form box appears at the bottom of the page and refuses to let me use my original embedded form for uploading.
When the file attempts to upload, I receive the following error: “Unable to insert item into DB! Column ‘file_hash’ cannot be null”.