Select, Shift/select or Ctrl/select your chosen entry/ies then, while holding the mouse button down, drag it/them to a new location in the current list.
If you want to move entries elsewhere in the model, open a secondary window and drag and drop them between windows.
To make the dragged item(s) descendant(s) of the destination icon, hold the shift key down while dragging. We call this 'Push down'. BrainStorm will not let you drop entries into an empty entry. In fact, you can drag entries to the heading to put them into the list to which the heading belongs. We call this 'Push up'.
You can even move them between concurrently open models, but don't be alarmed if the entry colour changes - if they are transparent they will adopt the colour scheme of their new home. See Colours and fonts for more details.
Read only entries cannot be moved in this way. If one or more is in the selection to be moved, the operation will be refused.
You may prefer to use Alt+Up arrow or Alt+down arrow to 'nudge' a single entry up or down the list.