If you try to use the Make Object's Layer Current button from the Layer toolbar or try to execute the DrawOrder command from a menu selection [such as the right click context menu] and you get a message saying that ai_molc or ai_draworder are not defined, then you have a problem with loading the MNL file which defines these functions. An MNL file is a text file that contains LISP statements, including function definitions, that is loaded "automatically" when a menu file [2005 and earlier] or CUI file  of the same root name is loaded. This is a handy way to make certain that functions used by your menu files get loaded with the menu.
If you have customized your menu or CUI file by either starting from scratch or by copying the ADT.mnu or ADT.cui file and renaming it, you also need to copy the ADT.mnl file and rename it with the same root name, as well, to get all of the functions defined therein to load when your customized version of the file loads. If you have already set up an MNL file for your customized menu, but started from scratch, you should copy the contents of the ADT.mnl file into your custom MNL file so that you get the out-of-the-box MNL functions along with your own custom functions.
If you have not customized the ADT menu or CUI file, then check to make certain that the ADT.mnl file exists, in the same folder as the menu/CUI file, and that that folder is in your Support File Search Path on the Files tab of the Options dialog. If it does exist, open the file [use Notepad or any other plain text editor] to see if the c:ai_molc and ai_draworder commands are defined. You may need to do a repair installation [or try searching for the adt.mnl file on the installation disks] if the ADT.mnl file has been altered or corrupted.
The following commands are defined in the ADT 2006 MNL file. If any of these are reported as not defined while using ADT, check that the MNL file[s] associated with the menu/CUI files you are loading include the ADT.mnl file or copy of it [or its contents]: