Got eCS installed on my (all-SCSI) desktop by making modifiable diskettes from CD1, entering "basedev.aic7870.add" into config.x and copying that driver onto the diskette. Rebooting after phase 1 hung the system, until I added that same line to config.sys. Then things went along as advertised.
For my 16MB ram laptop I made diskettes from CD2 and installed much like the Warp4 installation. Following that I ran convert.exe and now have a eCS desktop there also.
So -- Yes, finally, I seem to have some luck installing eCS. Now I will just play with it a while, and decide whether or not it is an advance over Warp4 w/FP15.
Thanks for your interest and help.