Bios Flashing - Please help

[Reminiz]

I've got a PAL VA1 DC with custom bios chip (from aliexpress, one of those MX chips).

So I desoldered my original bios chip and soldered the new one in its place, with the wires to the pins following a YT guide. On bootup i get the PAL logo as normal, it then looks for Dreamshell boot, then takes me to a menu with "Boot to CD" "Boot to RAM" both greyed out.

I purchased the Dreamshell disc and SD Serial adapter. So what exactly is on my Bios chip? The Aliexpress product mentioned Region Free and Dreamshell.

Essentially all I want is region free without the need to use a boot disc, most of my physical library is Japanese games and I only own one PAL disc. I don't have a need to play back-up burned discs (at least not at the moment).

So whats the process of flashing a new bios to the chip? Do I need to at all?

One more t hing, My GDrom won't boot games, it used to pre-bios chip install, disc won't show up in GDPlay in Dreamshell. Any ideas what I should check? Disc spins up fine but nothing comes up. Thanks.