The -dev version has been recently promoted to stable, so both versions of the EmulationStation package are now identical (for the time being, until more things are added to the new dev).

If ES crashes, the log will not be of much help, but a gdb trace (backtrace) might be helpful to see where exactly (in the code) the crash occurs. If you can reliably reproduce the crash, then it might be worth using gdb and capture the trace:

gdb -q /opt/retropie/supplementary/emulationstation-dev/emulationstation - ex run # if there's any crash, gdb will report it and show a prompt thread apply all bt