Hi Peter
We did not install liveCache as LCAPPS are not released for AWS. But I assume that they will run, I just would not recommend that you use the instance for production-like scenarios.
In order to proceed, you have 2 options, depending on your frontend.
Coming from a Unix-like (Linux, Mac) you can ssh -X or ssh -Y into the server and start sapinstgui on your X-Window.
On WIndows, you can start sapinstgui on your Windows box (get the most recent Windows SWPM from SMP, extract and locate the sapinstgui in the root extraction dir, double click and connect against the backend IP)
Caveats: if you have deployed public, you need to open port 21212 towards your network from the instance properties in CAL console. You can find the access points by clicking on the instance link in CAL Instances display, then Virtual Machine tab.
You will need to give the root user on the Linux box a password so that sapinstgui can properly operate.
I hope this helps
Manfred