Assuming you've done it all right (tutorials on ####://www.psxcopyworld.co.uk ) - which may be an irrelevant point for the reasons explained below:

1/
I don't think that modchip boots DVDRs. The first available PAL modchip to do so was NBEO2.2

2/
AR2/1.3 won't boot DVDRs when you get the right modchip. It has to be AR2/1.7 or 1.9

3/
Devil May Cry has a very large Table of Contents. What were you using that has a larger TOC to act as your PAL Original DVD game? Well it won't work anyway unless I've underestimated the modchip.com chip.