Download: Easier Mini Beam
This mod increases the Mini Beam length by 2 pixels, from 45 to 47 pixels.
This makes lining up 4-room swipes much less fiddly, without allowing you to hit any additional rooms.
This only changes the Mini Beam on Stealth A and C. It doesn't change enemy Mini Beams, as that might let them hit additional rooms with some of their swipes.