You can try forwarding the below list of domains for your IT team to whitelist on your network/firewall:
cdn.ipaper.io
viewer.ipaper.io
embeds.ipaper.io
admin.ipaper.io
ipaper.ipapercms.dk
tools.ipaper.io
docs.ipaper.io
help.ipaper.io
spf.ipaper.io
ftp.ipapercms.dk
All domains should have ports 80 (HTTP) and 443 (HTTPS) open.
If you use iPaper FTP server (ftp.ipapercms.dk), you should also open ports 20+21 (FTP).