Sounds like you need to reduce the polygons to something that Poser could handle. Even if your target application can handle a bloated model it is still a good idea to keep the polygon count as low as possible without reducing too much detail.

I don't have Carrara but most modellers have similar features.

1. Save a copy of bloated model with new name. Load it into Carrara.

2. Check the statistics/properties/info or what ever Carrara calls it that allows you to find out how many polygons you have. This is the number you have to reduce.

3. Find out if you have any polygons with more than 4 sides (also called edges). Earlier versions of Poser can only handle triangles (3 sides) and quads (4 sides). Don't know if latest versions can handle more.

4. Look for parts of your model that are mostly flat and start merging polygons. Read your manual to find out if there are short cuts to reducing the polygon count without making the model ugly. Sometimes better to do by hand since most poly reducers make geometry messy. Also consider simplifying parts that are not going to be seen often or in close ups.

5. Once you got polygon count down as much as you can stand check again that you only have tris and quads.

6 . Export to DAZ Studio and Poser to see if things are better.

7. Repeat as needed.

Hope this helps.