The eid/ directory contains mostly two-column tables of ETCSL IDs for each text.
The first line gives the Q-number and the ETCSL text-id.
All remaining lines that do not start with '$' give the ATF line number (i.e., the number of the line in the file, not the manuscript line number given at the start of the line) and the ETCSL line-id.
Lines starting with '$' either give an extent in column one along with the '$' and a type in column two, either "blank", "fragmentary", or "blank". If the ETCSL gap comment contained "approx" this is added in column three.
If column one has '$$', column two is the literally dollar line--this is used for $-lines that probably aren't needed for translation alignment but are kept in the .eid file just in case.