Microsoft implemented a series of hotfixes that limit the effect the flag set by EasyBCD has on the system. Certain types of unsigned drivers may be loaded with that EasyBCD option, others require you to manually press F8 at boot.
This is MS policy and there's nothing we can do about it.
Is it not possible to reproduce the effect of choosing the F8 boot option by reprogramming easyBCD? I asssume that this F8 command is sending a different command to vista after the hotfix.
I assumed that as you seemed to have discovered the previous one you might have been able to discover the present one? One must assume that MS have taken steps to hide these commands - maybe even encrypted them!