This study continues a series of articles devoted to the operating features of ion-optical devices with periodic electric power supply and constant homogenous magnetic field, used in mass spectrometers. It has been shown how the structure of combined ion trap stability diagram is changed when the trap configuration deviates from the ideal one. The influence of an angle between the electric field symmetry axis and a magnetic field direction as well as the influence of the electric field asymmetry on the pattern of stability zones were found. The results obtained are worthy of use both for estimating the impact of manufacturing defects and for designing new nonclassical ion traps.