The Fermi Bubbles and GeV excess: signatures of new astrophysical phenomena, or mirages of model incompleteness?

The Fermi bubbles and GeV excess are prominent residual features in the high-energy gamma-ray sky located in the direction toward the centre of the Milky Way. Their origin remains unknown, but it has been suggested that they may be connected phenomena. The robustness of their spatial and spectral characteristics have been strongly asserted by many researchers. However, I will discuss in this talk why the robustness of their characteristics, and if there is a basis for any connection between these features, should be considered still open questions. I will also give an overview of recent efforts made by the GALPROP team to address central issues related to disentangling `new' astrophysical signatures in high-energy gamma-ray emissions, particularly from the inner region of the Milky Way, from artifacts induced by incomplete modelling of astrophysical fore- and backgrounds.