Following the recent measurements I did within the CMS collaboration I will bring up some still remaining open issues in closely back-to-back dijet topologies in 2- and 3-jet inclusive events. There are considerable differences observed (up to 15%) and 2- and 3-jet data is not described by any of the models considered simultaneously. Also the unexpected behavior of Madgraph interfaced with Pythia8 will be address for 4-jet inclusive topologies. Preliminary studies suggesting a not proper merging as the source of the differences will be presented. An outlook and prospects on an exhaustive phenomenological investigation to address these issues within the Lund MCnet node will also be given.