i couldn't save an empty document,a new document with only a few objects too.

when i try to save the date that my design,and push the button ''save'',then my computer was like freezes,and the situation never changed,so then i had to do forced termination.Do you understand my situation??
P.S I purchased the software at the Apple Store.

hi,i didnt know why,but i can't save my date of the sweet home 3d.
my computer is mac book pro.Please answer.
detail
processor:2.5 GHz Intel Core i5
memory:4 GB 1600 MHz DDR3
graphics: Intel HD Graphics 4000 1024 MB
software:OS X 10.9.2（13C64）