Hi,
this is not an xPilot support forum, you should access their Discord to talk to their developers and users.
but have you tried using a (reputable) VPN? Sounds like an issue with your network.
This is a livery for the TorqueSim CJ525, inspired by https://www.jetphotos.com/registration/OE-FGC
To install, extract the zip file into the "liveries" folder.
You can change the registration using the TorqueSim tooling.