Sorry, it's not possible.
The avast! boot-time scanner is a special NT module - which can be executed before the full OS is loaded. The aswQuick program, however, is an ordinary Win32 application - it cannot be started that soon.
I don't know for sure, but I think the boot-time scanner doesn't support the special areas (such as the scan of "startup" items). As I already said, scanning the memory doesn't have much sense at this moment (i.e. it's not supported either I guess).