getting zero k file when using put url binfile in standalone app

[Colin Holgate]

I'm trying this as a script in one mainstack, with the goal being to create and jump into a copy of another stack:

on openstack
   set the defaultFolder to specialFolderPath("Documents")
   if there is not a file "AppStack.livecode" then
      put specialFolderPath("engine") & "/AppStack.livecode" into masterfile
      put specialFolderPath("Documents") & "/AppStack.livecode" into appfile
      put URL ("binfile:" & masterfile) into URL ("binfile:" & appfile)
   end if
   go stack specialFolderPath("Documents") & "/AppStack.livecode"
end openstack

The "AppStack.livecode" file is included in Copy Files. If I run it as iOS, everything is fine, but trying it in LiveCode, or as a standalone app, and the "documents" version of AppStack.livecode is created as a zero k file. Trying to do the go stack line gives a result that says the stack is corrupted. I can see in the standalone package that AppStack.livecode is in the Mac OS resources folder. Its file size is smaller than the original stack, but it's a lot more than zero k.