I was travelling for past month and most of the time I did not have access to internet. While running XDK in offline mode it crashed almost 100% when I switch the debug mode in the emulate tab. I think the problem might be that internally XDK still looks for internet from time to time even after pressing dismiss button at first error.
Sometimes XDK also crashed while I try to edit the code. My project is not that big only 500-600 loc and 20-30 assets
I am using XDK 3357 with phaser.
Unfortunately, at this time the only thing you can do reliably when not connected is edit your code in the editor.
Sorry for the inconvenience, I know it's a pain. I'll relay your feedback to our team.