So, I haven't done anything with OpenDCL in a while and I'm trying to get the latest runtime for 2010. Reading on here, looks like the only way to get it is to install the runtime using the *.msi? What happened to the ARX?
Problem is, I've developed several lisp for Acad LT using Lt-Extender and OpenDCL. The runtime doesn't seem to install anything that will work with this setup...
You can install the MSI, then get the needed .arx (and language resource DLL in the appropriate language subfolder) from the Common Files\OpenDCL Runtime folder.