using keyboard entry (a rollout in the creation panel) and the click on 'create' or with maxscript e.g:Box lengthsegs:1 widthsegs:1 heightsegs:1 length:50 width:50 height:50 mapcoords:on pos:[0,0,0] isSelected:on
There is no difference between using 50 Unwrap Modifiers and using one, collapsing, using another 50 times...you can inspect 50 different Map Channels with one Unwrap Modifier, but you can edit only one...