Can't Import LEADs, ACCOUNTs, CONTACTS, etc.

I have a LEADs file (exported from SF to csv) that I'm trying to import into ZOHO. All fields are mapped and I get no error on submission. However, I get no confirmation email that the import was successful and the import doesn't show in Import History. Of course, the data doesn't show up in LEADs either.

I've seen several questions on this in the forum with support requesting a copy of the file. I sent an extract to support@zohocrm.com yesterday, but I've not gotten a reply. I've now made several attempts to import. This is a show stopper for me, I cannot migrate from SF and upgrade my ZOHO Account without the ability to import LEADs, ACCOUNTS, OPPORTUNITIES, etc.

Please advise. And post to the forum the solution (if its a generalized one).