I've attached my Move_in_axis.lsp, It's a bit clunky and redundant but has served me well for a couple of decades. Drag and drop the lisp into the drawing (or autoload if you want). Let's say you wanted to align the bottom of one solid with the bottom of another. Type in the command (from below) and pick the point you want to move (bottom corner for instance) then select the point it's supposed to align with. Be sure you know where your USC will take you!
So, you have 7 solids and want them to align on the same Z-plane. Move the UCS to a point on the base solid that you want others to align with. that point should be for instance 12,4,0 (zero being important here). Now, M2Z, select object, select point. Enter, repeat.
There are commands in AutoCAD to do this that are easier if you're used to them. But I've found that "MNZ click click" is pretty easy too. At any rate, it's free, it works. Who can argue!
Have fun!
Don
The commands are
MNX - move in X-Axis
MNY- move in y-Axis
MNZ- move in z-Axis
MNXY- move in X-Y-Axis (filters out any z component
M2Z- move to Z-axis
CNX- copy in X-Axis
CNY- copy in y-Axis
CNZ- copy in z-Axis
