Problem with zmodeler 1.07b

Guys,

Can someone help me with a couple issues Im having?

- Whenever I export an object from zmodeler in gp4 format, It becomes transparent when opened in gp4 builder...how can I fix that?

- Another issue that Im having is that zmodeler refuses to import the gp4 files - whenever I try to import a car, for example, I always get an error message...is there any good tutorial that I could follow to import/export?

Thanks!