If you add a struture example it would be perfect. After read your explanation and documentation, i understand that my initial problem was i have to create a specific folder for my template. I didn't understand this just reading documentation. After read it first time, i post "logo.gif" in devpi_web/static and modify devp_web/templates/macros.pt. So if this point is more precise (with structure example) i think it will be OK. Perhaps one more thing: you talk about "logo.gif". It could be nice to add main supported formats if there is not only gif.
In all cases, very nice work.