The bug icons are very cute and very well done. However, before they are used to represent the concept "bug-report" I would like to argue that the images map to the concept through the polysemy of the word "bug" in English ("insect" and "defect in a program"), and so they won't work well for people that speak other languages. And adding a verb to the image by making the bug appear writing a paper might not be cross-language grammatically correct. In Spanish, as an example, program bugs are commonly called "fallos" (faults), so I don't believe that the image of a cockroach writing on a piece of paper will make you think of the phrase "bug report" and then convey it's meaning, but more likely, to make myself understood, it will make you think of the phrase "ant writing" and then leave you a bit disconcerted.