Why allocate a new Perlin then delete it in one function? It's slower, and you risk leaking memory if Get() threw an exception, you may as well just have it as a local.
To debug a plugin, make sure you've built a debug runtime version of your plugin and that it's in the IDE's runtime plugins folder. Then, locate the Temp.exe that the IDE creates for previews, which should be somewhere under your Users Appdata folder (eg. C:\Users\<username>\AppData\Local\Scirra or something like that - AppData is a hidden folder so you need to make sure Windows doesn't hide hidden folders). In Visual Studio's project settings, set the debugger target to be that Temp.exe file, then click Start Debug. It should launch Temp.exe and start debugging your plugin.
Note Temp.exe is replaced every time you preview, so make sure if you change the .cap you hit preview, close it, then start the debug. Also, if you change your code you need to rebuild your plugin and put it back in the plugins directory, otherwise you'll get a "symbols don't match" error.