Need Help with AutoLISP for HVAC Ductwork

[AceV]

Hello,

I am new to AutoLISP and I have been trying to find/create a code that will simplify drawing HVAC ductwork. I have found an existing code from an autodesk discussion group: http://forums.autodesk.com/t5/Visual-LISP-AutoLISP-and-General/Doubleline-Duct-lisp-routine/td-p/3198454 (The last posting: DUCTNEW.lsp) This code is meant to do exactly what I am trying to accomplish, except that when it prompts "continue, split, double-split, transition" the only command that works properly is . Any tips or help would be greatly appreciated