Xiste, it worked for me on my iMac so could you try with some other SH3D files?
To remove the last version of the plug-in, remove it from the plug-ins folder of Sweet Home 3D and restart it. This folder is shown when you click on any SH3P file listed in the Plug-ins section of the Libraries in use pane. The latter pane is displayed by clicking on the Libraries... button shown at the bottom of Sweet Home 3D About dialog box.