JOSM question.
I installed 2 plugins as per instructions :
BuildingsTools
FastDraw
Both plugins are visible in their correct location ~/.josm/plugins
However, they are not visible anywhere in JOSM itself.
What’s next?
(OSX 10.9.5, Java 7)
Are you sure that building plugin is not shown on the left screen margin in the http://josm.openstreetmap.de/wiki/Help/EditToolbar ?
And in JOSM inside help menu there is an entry Status Report or similar … there is a list of all loaded plugins. What is there in your JOSM?
The problem was finally solved by reinstalling JOSM, reinstalling all the plugins and restarting JOSM 4 times! 
Not sure what caused the problems.