There are a couple ways to "import". One way is to bring in characters one at a time by dragging from the browser (equivalent to poser library) and dropping each item into the carrara window. This way always lets you at least see the character and grab and move it quickly. Drag and drop only! A double click on a browser item opens a new window.

Another way is to file import an actual poser scene. Be sure your default Carrara opening scene is medium-sized. The poser scene then should look normal.
If you open the poser scene into a carrara scene that is larger (like a terrain), the poser scene is tiny (room sized) within a space that Carrara is treating as world-sized. In the properties pallette you should see your poser scene listed as an item within the carrara scene. Click on it (or any item in it) and then look in the motions tab. Here you will find the x,y,z coordinates of your scene-within-a-scene. Here you can type in new coordinates so that you need not even drag your scene to where you want it to go. It will snap there on its own. 0,0,0 is always centered in Carrara's medium (room-sized) default window.