for me the simulation finishes without problem, using the same antenna. Did you change anything else regarding the original parameter setting?
To your second question: First it seems that you chose a network source that is not supported. If you want to use a predefined network, you have to set LTE_config.network_source = ‘generated’ and LTE_config.network_geometry = ‘predefined’. And secondly: Your original problem doesn’t seem to be related to the network source/geometry.
Possibly the best idea might be to reset to a fresh version of the simulator and see if the demo simulation with femtocells finishes without errors.