Configured autostart works this way.
-We need to edit autostart with this command: sudo nano /etc/xdg/lxsession/LXDE/autostart
-At the end add the line: @/usr/bin/lxterminal --geometry=90x35 -e cgminer (The parameter "geometry" is to set the size of CGMiner, so adjust the parameter to your needs)
Then if I remove power cord from Raspberry PI and Butterfly device, simulating problem with electricity.
Then after put power cord back and reboot, the "USB device in use" is displayed in CGMiner.
And I need to remotely login with TightVNC to Rasperry PI and remove the file /tmp/cgminer-usb-1-4 to allow CGMiner access to the connected Butterfly USB device.
Then CGMiner finds and uses the device.
This issue prevents auto start to work properly, since delete of the file is needed.
I tried even to try autodelete such file prior start of the CGMiner, during reboot.
But it somehow did not help.
I am currently using Minepeon distro and CGMiner there.
There seems not to be the observed issue.
That sounds suspiciously like you actually have 2 cgminers running at once without knowing it. The file is a red herring by the way and not the actual problem.