The .zip is just unfavourable done. Open the "bookly-pro-addon-1.8.zip" -> Then open the folder "bookly-addon-pro" -> Then there are 2 folders. Make both of them a seperated .zip and install them on your wordpress.Hi - when i try to upload the zip, it says: no plugin found and upload failed - how can that be so?
Or just paste the two folders via FTP in the "wp-content/plugins/" directory.