Help with magento 2.0 data migration script (migration from 1.7.02 to 2.0

We need some assistance with migrating our magento 1.7.0.2 database with the official magento data migration tool ([login to view URL]) to our new magento 2.0 system. The following error occurs while running the script: ------------------- [2016-01-11 16:40:15][INFO][mode: data][stage: data migration][step: Url Rewrite Step]: started 24% [======>---------------------] Remaining Time: 25 secs ------------------- Here the script stops and outputs: Error Exeption Undefinied offset: 0 The error is related to the table "core_url_rewrite" in the magento 1.7.0.2 database - if we drop this table the script runs to the end but of course all urls are bad. We need a magneto 2.0 specialist to show us how to fix the problem. Also this is a starting project as we are searching for a magento 2.0 freelancer for theme adaptation and some magento 2.0 programming.