The xtcom is from the electrodragon blog post about cloud update http://blog.electrodragon.com/cloud-upd ... p8266-now/
Works fine from virtualbox though.
I have the esp8266 flasher but it crashes at exactly the same point as the python based tool. Was hoping XTCOM was a 3'rd tool that might work better. (I have two bricked modules at this point)
Now I've searched a bit more where I read abou the XTCOM, I think that's a different tool, perhaps something generic to flash devices via UART, anyway here's the link if you wanna try it out, it's from the russian esp8266 community: http://esp8266.ru/download/esp8266-utils/XTCOM_UTIL.zip
Let me know if you have any luck with it!