The style "object without fill", in contrast with its name, sets a colour for an object. To reproduce: draw a rectangle or another closed shape, set the area fill to "None" and then assign the style "object without fill": the shape will again have an area fill. You will see the area fill, too, when calling "modify" for the style. The style was still correct in 6.1.5.2
I forgot to say that the bug is still present in Version: 6.4.0.2 (x64) Build ID: 08d19fecdc7a2298d051e19cfdb7c35544855fc3 CPU threads: 4; OS: Windows 10.0 Build 17134; UI render: GL; VCL: win; Locale: de-DE (de_DE); UI-Language: en-GB Calc: threaded
That is duplicate to bug 123841. Workaround: Take a new document, modify the style "Object without fill" so that the fill in NONE, save the document as your new default template. *** This bug has been marked as a duplicate of bug 123841 ***