How do I know which firmwares from other manufactures that are
compatible with my player.

I have an Eltax MovieStar with this specs.

Versio : 05.00.03.05
Sub : 00.00.00.02
8032 : 05.00.03.05
Servo : 18.04.00.00
RISC : 05.00.03.05
DSP : 03.03.01.05
Firm ID : MEDIATEK
File : MTK.BIN
Pass : 0,0,0,0,0
Flash : Type 800 (16bit)

Thanks