PSP - 3.52 M33 Easy Installer

I've just tried to upgrade my 3.10 OE-A to 3.52 M33, using the easy installer provided on psp-hacks.com.
I can't get it to work. Here's what I did:
1) Formatted my memory stick
2) Restored the PSP to default settings
3) Ran the program. It asked me to choose my PSP directory, and I did.
4) On my PSP, in the GAME menu, I ran the 3.52 M33UPDATE flasher.

After I had completed the last step, then screen went black. I tried to put my PSP back on after 20 seconds or so, but it wouldn't work, at first. After several tries, it did.

According to the system info, my firmware is still 3.10 OE-A. The only difference from before I tried to install, is that I freaking can't access Recovery mode any more.

This is what the "PSP" folder on my PSP looks like, as of now. I have put the files (well, file, really) in parenthesis The rest is folders:
COMMON (Empty)
GAME (Empty)
GAME150 > M33 UPDATE_352 (EBOOT.PBP)
GAME310 (Empty)
SAVEDATA (Empty)
SYSTEM (Empty)

As you can see, there is only one file. Namely, EBOOT.PBP, which lies in the M33 UPDATE_352 folder in GAME150.

I am in desperate need of help. I'm considering skipping 3.52 M33 after this, going with 3.40 OE-A instead (though it would be more optimal to get 3.52, of course), but I want to check what kernel (whatever that is) I'm using before continuing with any upgrade, and I can't go into Recovery mode.
Does anyone know what I should do to get the upgrade to work, or/and be able to enter Recovery mode again?