Robert,

Arrows do come in with a tiny (invisible) thickness by default. Draw the arrow and adjust the thickness and make sure the opacity is 1 (although it sometimes does not show the current value). Once it is adjusted, it seems to "stick" after that. Same for other objects. I hope this helps until they fix it.

Regards,

Neil

I'm sorry if I was too vague in the description. I have no problem with generating all kinds of graphics programatically in Mathematica but when I try to use the drawing palette on a 'new graphics'-pane it doesnt work. If I click (or double-click) the rectangle tool and try to draw in the graphics window I get nothing. At first an orange shape is shown but it disappears immediately when I click something else. If I change to the select/move/resize-tool I can mark an invisible object that I apparenty managed to draw after all so I guessed that it had something to do with default opacity like in this posting . I can change the opacity for some invisible objects so they appear (like rectangles) but it doesnt work for arrows. Since I found a posting on stackexchage directly I thought that this was a known problem and therefore I was a bit vague, sorry for that.