Installed SQL-Ledger in /opt. Imported SL backup file (from a production installation) and verified that the system was usable.
The phrase "copy the files from the tarball over the existing SQL-Ledger directory" was not as clear as I might have liked. But I copied each LedgerSMB file/directory to the SL directory. I then executed the SL2LS.pl script.
When I went to my SQL-Ledger site, the LedgerSMB login screen appeared. Success was short-lived, however. I entered the user id and password that I had used to access SQL-Ledger and got an error message "Error! Access Denied!"
Thinking that I needed to set up the user again in LS, I went to the admin login. It immediately asked for an initial password. I entered a password twice and clicked 'change password' and got an error message "Error! users/members: Permission denied".
I am now locked out of my LS system.