[charlie_ps2]

There is nothing about the Messiah that requires laser adjustment subject to what I describe below.

Messiah (and it's not alone) allows DVD-Rs and CD-Rs to be booted. generally, CD-Rs are not a problem for the laser because the disk is not as densely packed as a DVD-R.

So if problems occur, it's with the playing of DVD-Rs. Problems are more likely if:

1 Your PS2 is old (v1/v2/v3) AND well used (esp. DVD Movies)
2 You have previously installed a NEO2.2
3 Your lens is dirty
4 You have used the Knife trick and touched the lens mechanism

If import originals play OK with Messiah or if CD-Rs play OK, your install will be fine.

So then you clean the lens and try again. If no go, you recalibrate the DVD laser by reducing the resistance by no more than 10%. If that works,, it'll fail eventually and you will have to replace the laser ($65) as you would if the recalibration doesn't work.

Hope that helps.