As Arsalan said, we don't know how your network is set up. If your router/network properties of vmware are correctly setup, the vm image pretty much works right out of the box (I'm also using the vm image, via vmware on win10x64). First check if you're able to access your ossn site from the machine running vmware/virtual box (not from within the virtual machine). For example, if your IP for the virtual machine is 192.168.0.111, first make sure you can access this from the host machine (for testing purposes, you may want to temporarily set your ossn config to use this private IP url, i.e. http://192.168.0.111). Once you verify that you're able to access the site through a privateIP, you just need to route requests from the Internet to that IP appropriately. This can be accomplished with port forwarding, but in my experience, it doesn't always work and is a real pain to get working with vmware. A much easier solution is to use a reverse proxy to make your private IP internet-accessible, which can accomplished very easily using a reverse proxy such as ngrok, localtunnel, serveo, probably some others I'm missing. I use ngrok and it's really easy to set up, you can either use it with a custom hostname (read the docs at ngrok.com for further info on setting up custom hostnames, this allows you to use your own domain name) or will assign you a random subdomain address under *.ngrok.io. One advantage of this solution is that ngrok also provides https urls, even if your webserver isnt set up to serve over ssl. This is useful for things likr webhooks that today usually require https urls. This is the command I use to start ngrok:
ngrok http -hostname=myhostname.com 192.168.45.128:80
You can find more info on that particular reverse proxy at ngrok.com. you may also wanna check out serveo.net and localtunnel.me.