Option 55 only works with VASP and SIESTA. The only difference between options 55 and 5 of the main menu (Section 3.6.1), considered above, is that the density file is implied only3.12, and the second part of it (containing the spin density) is read in, the first part (containig the total density) is skipped. After the spin density is read in, the same menu as in the case of option 5 is opened, so that you can refer to the previous Sections completely.