what circumstances? all we need are the dae/tdm drivers from that version
As I stated, the "TDM" mixer windows with TDM plugin inserts does NOT exist no mater what drivers you load/replace/modify on the VST versions, so it is obviously "cooked", compiled, baked, whatever into the main application. You are implying the main versions (Audio, Audio XT, VST, Audio 3.0) are all the same basic code, all modular, and easily manipulated. Unfortunately, this is so far from the truth; each respective version is a totally different stack of code. The audio engine from VST 4.1 and VST 5 was re-written because after various "porting" the code got sloppy. Their pinnacle for OS 9, VST 5/32 definitely holds it's own in "sound quality" almost to today. With "true tape" files (32-bit audio) it is one killer DAW and was the first real attempt that was viable when mixing in the box (without outboard gear). Apogee dithering, real metering, better plugins (with UAD-1 and powercore), a new audio engine, and other items really made us think at the time that we were finally getting pro results.