Oh, I see You are induced in error by an old page in vrmlworld.net site.
ABNet is actualized often and does not need the activex thing anymore. Today it uses flash and works on internet explorer (also in Firefox and Chrome if you install IE Tab plugin for them). I am the guy that takes care of the server and developed the interface you see in ABNet (called babelx3d and that may in the future be adapted to other x3d/webGL systems
You probably seen an old page made by rick that he never removed (and is confusing not only you). Nor you need to install the old ABNet server on that page just use the ABNet public server that is updated as well as the interface. By the way, a new development we are working on is the fly mode
for avatars in babelx3d, not yet seen on VRML/x3d worlds
If you have a world just launch it here:
About users, well, people come there frequently but not as in old bxx times and new worlds are coming also. If you Just go there and get out immediately, probably wont find anyone. But if you open a world and wait for some time you might find another soul visiting
see you there,