command to move all objects to same plane

Assuming all items are at the same level to begin with, yes. But to ensure
that they are all on the same level you would "Flatten" everything to 0 Z
then move them up 25' Z ...

^C^C_select;all;;move;p;;0,0,1e99;;move;p;;0,0,-1e99;;move;p;;0,0,25';;

 

Ok , I'm starting to see why things work the way they do....

Thanks for the help....

On a side note, Have a suggestion for a good lisp book to start with?

 

I keep a copy of AutoLISP Programming Principals and Techniques in my
case.... written by Rob Rawls and Mark Hagen ISBN 1-56637-417-0... it's
written for R14 but few exceptions everything works the same (ie -insert vs
insert)... you'll see a copy on eBay pretty cheap every so often. Here's one
of many great sites http://www.afralisp.com/ .