Indeed, the problem is solved by including the [font=courier new]pipette[/font] cursor icons.


Here is the derived version that allows to create lights and modify their sources.
FurnitureLibraryEditor-1.28_derived.jar
FurnitureLibraryEditor-1.28-src_derived.zip

Note: As it is not possible to attach the files because apparently their sizes exceed the maximum allowed, I put links to SourceForge.