Knife trick boot should work, but it doesn't
This is the situation:
I've got an unmodded PAL V3 PS2,
a recently bought PAL Action Replay V2,
a good knife tool for performing the knife trick,
a TV that supports NTSC,
an original PAL DVD game with a large TOC (Devil May Cry),
an original copy of the Asian NTSC-J version of FFX International.
Using the knife trick,
I can boot backups of my own original CD-based PAL games,
I can boot both PGEN and PS2Mame, which run just fine,
I can boot my own original DVD-based PAL games using a double swap with DMC.
The latter is for testing purposes only of course, I can boot original PAL DVD's without the need of the knife trick.
I figured that all this means I should be able to boot original imported DVD games. But FFX International does not boot. After the double swap and pressing X in the AR2, there's some disc activity and the screen turns black, but then nothing happens.
So my question is now: Where does it go wrong? What did I miss? It should work, at least that's what I figure, but nevertheless it doesn't.
Can I only boot backups of imported games? Or does my AR2 perhaps have some sort of limitation, seeing how it is a very new version? Or is it something completely different altogether?
Oh, and please don't tell me I should get a chip installed in my PS2. I'm looking into it, but it's very expensive here, so first I want to make sure there that there's absolutely no other way to do this.