I've been trying to get a good back up rig for my Kemper for some years. It's quite a tough ask. I can't really justify buying a second Kemper as backup because I am not a touring musician or an investment banker.
I have a laptop and was curious to see if I could use some of the equipment I have to make it a good guitar rig.
I basically used the VST Amp Rack which comes with Cubase. Ran an output from my interface into a Fryette Power Station and then routed that to a 4x12. To mimic a situation where I was playing live, I miced up the cabinet and recorded the output to get an idea of what the tone might sound like out front.
Here's my rig in action: