Hi,

the BlogML files should be exportable to XML file. After you create this XML file you can use Kentico Import Toolkit which allows XML file as a source of data. It maps xml columns to Kentico column. So before importing actual data you will need to create a document type which will represent your blogs.

How to create a custom document type is described here:
New document type

Then you can use the Import Toolkit to import your data from XML file:
Kentico Import Toolkit

The tool can import data directly from the database as well. So you also use this option.

I hope it helps.

Best regards,
Ivana Tomanickova