Cycle through autocomplete suggestions without arrows

Peter Gromov's answer brought me to a satisfying solution:

In IntelliJ's settings, for Keymap → Editor Actions → Down I set a custom shortcut: Ctrl + J.

This way I can cycle forward through the suggestions.

Setting a shortcut for Down with Selection or Scroll Line Down in the IdeaVim-specific shortcuts did not affect the selection of autocomplete suggestions though.

The answer here: https://stackoverflow.com/a/9713306/2370679 led me to discover that Ctrl+n & Ctrl+p allow navigation of the auto-complete options without having to modify any settings