I am new there and I need some help for importing a wordpress blog.

I have a old wordpress 3.1 blog (no multisites) and need to move to new hosting (a sites under multisites). I don't have the access of database so I do a wordpress export.

Then I do the wordpress import as usual, with `Download and import file attachments` checked. My hosting a restrictive hosting so I need to do break down the process by keep on reloading the import page (step 2). After all done I found only the last imported images are attached to the posts, all other linkages are gone.

Question:

* does it matter that the attachment linkage is gone?
* If I want to re-attach the attachment to the origin post, any plugin should I use?