Shouldn’t be a problem. You can even try multiple times until you succeed (except menus stack up with each import but you can just delete the menu and do one last import). Try to import first without importing attachments and then you can try importing with attachments. If you have insufficient memory allocated to your installation, the import can fail badly every time you give a try.
If the import keeps failing, pls try increasing the memory as described here –
http://codex.wordpress.org/Editing_wp-config.php#Increasing_memory_allocated_to_PHP
If you still have trouble, pls email me the temp login to your wordpress install and I will try to see what’s happening. It is also useful to check for errors in the error log in wordpress install directory. Email me a copy of the same as well. Thanks!