If you access locally the application with 192.168.99.100:8080/Thingworx, this look like a host only adapter ip address , so it would not be accessible outside the local host machine.
If that is indeed a host only adapter, you would need to add a NAT adapter to your VM and setup port forwarding to forward port 8080 of the host machine to port 8080 of the guest VM.
In Virtual box you would do this with Settings > Network add an adapter of type NAT, press the port forwarding button to create a new rule.
or you might setup a bridge adapter that should then allow to see the VM ip on the local network.
Hope this helps
I work with Erik on this and I want to thank you for the answer. I tried to change the Virtualbox with the port forwarding NAT adapter and it worked! However, I was on a remote connection and could only verify that 127.0.0.1:8080/Thingworx worked. Next step is to see if it's also reachable from other machines in the network.
Also, I wanted to know what the difference is to setup a bridge adapter as was the other suggestion? And to set it up, do I change the "host only" or "NAT" adapter to a bridge adapter, or do I only have the bridge adapter?
The choice of using NAT or bridge is yours.
In NAT, the guest machine uses the host machine network and is not visible from the other machines (unless you set up port forwarding)
in Bridge, the guest will gets its own ip address and act as if it were on the local network (you do not need NAT and host only adapter in this case), and so directly accessible from other machines.
You can find more info on the Virtualbox site:
Bridge: Chapter 6. Virtual networking
Hope this helps