Did you unpack the plugin like this?
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Code
── RisingWorld
├── plugins
│ ├── GPS
│ │ ├── assets
│ │ ├── i18n
│ │ ├── COPYING
│ │ ├── HISTORY.en.md
│ │ ├── HISTORY.md
│ │ ├── OZ-GPS-Plugin.jar
│ │ ├── README.en.md
│ │ ├── README.md
│ │ ├── *.db
│ │ └── settings.properties
│ ├── shared
│ │ └── lib
│ │ ├── HISTORY.en.md
│ │ └── tools.jar
: : Alles anzeigen
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Looks like the class "com.vistamaresoft.rwgui.RWGui" is missing.
I think it should hang in "RisingWorld\plugins\shared\lib"
Maybe you can fix that with the info.