Hi,
The Matay DMA update never worked, only the DMA update from E3B works correctly. However I do not believe it is available at present.
Even without DMA support, the Prometheus is natively supported in OS4* for graphics (Voodoo, Permedia2, others may follow), ethernet (RTL8029), and also audio (ES1938 chipset only).
The mixer of other sound cards such as the Live!, SB128, and others is still supported, but no audio playback/recording can take place, due to lack of real DMA.
Regards
Ross
* Thank you to redrumloa for making this possible by sending me a Prometheus.