As requested, here is a summary of what I found out about drag and dropping files onto runtime applications. After receiving some insightful help from various folks, it does appear that the problem with runtimes that lose the ability to have files dropped on them is linked to the bundle bit. A machine that has MacPerl installed on it recognizes the runtime as MacPerl and allows documents to be dropped on it. When you move the runtime application to a machine without MacPerl, it gets confused and, while you can double-click to start the application, it will not recognize drag and dropping on the runtime. This can be fixed by rebuilding the desktop of the volume you've moved the runtime onto. It also blows away the nifty little camel icon(?). I am still vauge as to why this is the case and would appreciate some more insight into how this works. But even more important: Is there a more convenient way to get a new volume to recognize the runtime rather rebuilding the desktop. While this fixes the problem, it isn't a very good solution for an application that needs to be able to be copied from computer to computer without a lot of tinkering. Any ideas? Thanks David