> One thing I have not done is to start a new drawing entirely, where I > might add the same part, and observe if the rails are floated. > > Stay tuned. > > And if you have any advice, please reply. > > Thank you. > I have experimented considerably now. It seems that at least one digital part on a schematic must have its two power pins explicitly tied to the rails. After that first part is so tied, the ERC finds no errors. Apparently, the remaining devices' power pins are implicitly connected to the rails.
However, it gets worse if I include my new library in the set of libraries that my project can draw upon. Since a like-named part apparently exists in the new library, compared to the old library, it seems the characteristics of the part in the new library "contaminate" the characteristics of the part in the old library. I could investigate further, but it seems this program is rife with beta-like bugs.
