I had no experiences with your particular error, but had problems when compiling with error ...something ... negative : -1... I solved this error by renaming lisp filenames to something short like : 1.lsp, 2.lsp, ... Then when compiling passed I also renamed x.vlx to something more intuitive like what it does : TSP-fast-new.vlx or TSP-fast-new.fas... I hope that your issue could be something that simple, but I don't know... Try it, maybe it helps after all...