When I click on "fbclear" in the "Raytrace Control Panel" I receive an error:
"Rt Error: couldn't execute "fbclear": no such file or directory."
Do I have to have "/usr/local/BRL-CAD/bin/" in "PATH"?
Yes, there are a few automatic commands that still require the bin dir to be in your path. It's been a slow progression to convert all of the various "under the hood" commands over to not use path searching.
After your reminder, I updated the remaining dozen or two that still utilized the user's path to no longer use the path. This should be in the next release of BRL-CAD.