May be your disc... have you tried running any legit PS1 games that are of the incorrect region code (Your mod chip should allow you do play them)?
The screen goes black for a few seconds, then i get a screen showing the memory card " There is no data " and then the " Please insert Playstation or Playstation 2 disc" .
I have a SCPH 70004 and the game is Metal Gear Solid - PAL ( SLES_013.70 )
Tried with other PS1 games, same problem .
Since your disc is really scratched, you should try to get a good dump off the internet (But keep your original).
Corrupted game files may render your game unbootable, or may crash your game.
I tried playing a PS1 game that was burned into an Imation CD-R a few years ago recently, and it won't boot on my PS2 (No valid disc, and the laser trying to focus). Apparently the disc had gone bad (Never use cheap discs!).
What brand of CD-Rs are your using?
You can't launch PS1 ELFs or PS1 discs that way. The PS2 needs to be set into PS1 mode first, and this can't be done with uLE (Or by any program available to the public so far).
I even tried an alternate boot method .
In ULE you can launch the SLES file for PS2 games in CDFS and the game will start . I tried with my PSX game and ULE says " This file isn't an ELF "
You can't really use anything else. As stated in some other threads, the only way to play backup (Or games from other regions) PS1 games is to hard mod your console.
What can i use to boot PSX games ,since it is hard modded and recognizes burned discs ?
Unmodified SCPH-77006 with SM 3.6
SCPH-39006 with M-chip modchip, SCPH-10281 NA and refurb Seagate 80GB HDD
SCPH-10000 v1.00 with SCPH-10190 PCMCIA NA and SCPH-20400 HDD unit