Upon interacting with the finish editing button in the editing control panel, you were able to dupe items within a certain time frame.
The future of this plugin: I have been planning to re code the entirety of this plugin because of how poorly made PlayerWarps is. I have a better understanding of how to make object orientated plugins, and I will be re coding the PlayerWarps plugin so it's a lot faster when running certain functions. I plan the make all messages completely configurable (I don't know about the GUIs yet). If a bug happens to pop up before I'm done, I will try to patch it ASAP so no one has to deal with the bug.