I'm having this exact same issue. Bought the plugin but have no sampler to select mesh, and have an error message "To unlock custom features for loading images, sprites and meshes PopcornFX plugin for iClone is required.".
I've bought everything and tried everything like removing all the libraries then downloaded again, and removed then reinstalled the plugin and still get this message.
I'm trying to use a mesh emitter to eject shells from a weapon, but I can't do anything other than use the default shapes from the emitter.
I watched the video shared here, but I don't have whatever that is in the video and almost zero info anywhere on this.
Did you find a solution to your issue?