Seems that VarAC .adi data format requires data labels to be in lower case. That requires that ADIF Master be configured to use lower case. However, ADIF Master inserts a space following each data block within a record which VarAC will not accept. Since ADIF Master has been around longer and is in wider use, it would be great if VarAC would also accept an embedded space following each data block. The data block size indicator does not include the space.
I have a lot of digital QSOs logged by FLDIGI which also adds a space after each data block. I was able to adjust my log file so that the block headers are lower case and trailing spaces are removed. I can now access my full digital QSO history with VarAC. The "worked before" color coding applies to my full log and in Callsign History, I can see all digital QSOs including those made using FLDIGI.
It would be really nice if I didn't have to manually manipulate the .adi log file.