One way to disable the Session restore question (after the browser has crashed/been turned off hard) for Avant Browser is to delete the files that hold the session data.

DEL /Q "%appdata%\Avant Browser\*.opg"
DEL /Q "%appdata%\Avant Browser\reopen.dat"
DEL /Q "%appdata%\Avant Browser\pages.dat"

This can be scripted together with the launch of the browser so that batch(.bat) file could look like:

DEL /Q "%appdata%\Avant Browser\*.opg"
DEL /Q "%appdata%\Avant Browser\reopen.dat"
DEL /Q "%appdata%\Avant Browser\pages.dat"
"C:\Program Files\Avant Browser\IExplore.exe" %1

note: the %1 means to insert the first argument given to the batch file here. So if this is called “avant.bat” and you would call it with “avant.bat www.f15ijp.com” it would open this url.