Yes, you are right. As others said, you are running older AntTp version so it does not recognixe the mime typ for that file and loads it as bunch of bytes directly into website. There are 3 options:
- Upgrade your public AntTp gateway to latest version
- download it from commandline using for example wget
wget -O launcher.zip https://anttp.antsnest.site/012873cac6897439fc8dcad81f7be1ea344af0acf8a3dfda3e642208766e3eed/launcher.zip - Use latest AntTp on localhost and download via that.
If you manage to update that public gateway(anttp.antsnest.site), than everyone will be able to download it from browser.