This is a utility that is used to "lock" the whole drawing to prevent it from being altered or otherwise used if and when you have to provide it to someone. It is not unbreakable, but it does prevent casual theft of your work.
It makes an anonymous block your drawing and then makes the drawing an MINSERT. The result is that it is not possible to explode the drawing or write it out to a file where it can then be used without spending a considerable amount of time and effort. WAI-LOCKALL does not rename existing blocks or purge them out. As a result the person receiving the drawing can write out the normal block definitions from the drawing and steal the blocks you have spent time preparing.
You can add the VLX file to your APPLOAD list, or you can force load it in your ACAD.LSP or ACADDOC.LSP files, or you can add an entry to autoload it in your ACAD.LSP or ACADDOC.LSP file.
Simply enter WAI-LOCKALL at the Command: prompt, and follow the dialogs and prompts. MAKE SURE YOU READ THE ALERTS AND PROMPTS. You don't get a second chance.
If you inadvertently run WAI-LOCKALL on your working drawing, close AutoCAD and DO NOT SAVE the changes no matter what else you might have done to the drawing that you want to save.
Before you use WAI-LOCKALL, make sure you have tested it on a copy of the drawing, and NOT THE ORIGINAL. Only when you are satisfied with the results should you consider using it.
While all care is taken to warn users as to what WAI-LOCKALL does to a drawing, WAI Engineering cannot be held responsible for changes that are made to a drawing that then renders it unusable.