Hi, used MechaPwn 2.00 on a slim pal 9004, which is not compatible with freemcboot. used freedvdboot -which IS compatible luckily with my slim 9004- to change to dex region 9004 europe. afterwards, ps2 could only read original PAL games and nothing else, also not freedvdboot. I thought I 'bricked' my ps2 homebrewwise, being forever stuck on the DTL version. Luckily I have another fat ps2 with freemcboot which can't run mechapwn. I installed OpenTuna through my fat ps2 on a memory card and that way I could access ulaunchelf and reinstall mechapwn on my slim ps2 (phew). This time, I chose dex region 900x (1 or 2 can't remember?) USA and this time it booted everything, including backups. Only thing that was off was the PAL logo for PAL ps2 games, which looked corrupted. ntsc-u and -j logos were fine.
Just to make it easier for you, if you are going to use DEX on a PAL Deckard console, go to the USA DTL-H90001 region and you will not have problems with FreeDVDBoot or anything.
If you had read my previous comments you would have avoided so many problems you would know that you can damage the Fortuna, Funtuna, Open Tuna, etc. And if you don't have an entry point to ULE especially on a 90k without a chip or with another PS2 to be able to copy Fortuna. Well you were just screwed
Hopefully the Developer will consider our feedback and can give us a solution, it would be great to make DEX its native region.