Update I took the suggestion to use the docker image so I could use the latest release rather than the .deb package. I had to install and get some understanding of docker, since I never used it before.

I could not get the instruction provided by the website to work, most likely because the port for the http connection by a browser wasn't being exposed even though the instructions said it would be.

I then downloaded the docker-compose.yml file on advice from Eric Huelsmann, and then used docker-compose with that file to build the whole docker application. That didn't work, because the .yml file had a higher version number. After some trial&error, I changed the version number to 2, and then the build worked. (I first tried to comment out the version number as suggested in the error message, but that generated a few error messages about the file.) Now everything seems to work, but my firewall didn't like that one of the containers docker used the network 172.17.0.1 to operate. I then added a rule to my firewall to allow the network 172.17.0.0/24 to work.

Suggestion to developers: most potential users for ledgersmb are not developers and need an up-to-date installation package like a .deb package, They just want to use the product.