Here it is....
The Terratec Control Panel "Settings" shows "Source" as being WavePlay 1/2, 3/4, 5/6 and 7/8; "Port" as PCI 1/2, 3/4, 5/6, 7/8.
In Cool Edit Pro 2.0, I see Options/Device Order/Playback Devices as
Unused: EWS88D System Wave, S/PDIF, Wave Mapper;
Used: EWS Wave 1/2 [EV], 3/4, 5/6, 7/8. The EV means that, in Edit View, channels 1 and 2 are used for playback. This is accomplished by highlighting 1/2 in the "Use" column, and ticking the box below that says "Use In EV."
Recording Devices are set the same.
In Options/Device Properties try unticking "Try as WDM" if it's ticked, or vice-versa. You will need to do this separately for each track pair.
The Terratec manual (it's the same book for the EWS88D and the EWS88MT) says:go to Start/Control Panel/Multimedia/Audio tab and set the Playback "preferred device" to "EWS88MT Monitor WavePlay" and the Recording to "EWS88MT Digital Mixer."
Hope this helps. As I said, this all works fine for me.