auto_increment_increment issue CRM-7923
I have never heard of this before, but did track down the issue for you:

CRM-7923: Installation procedure relies on contiguous auto increment ids

Read the thread more closely to be sure, but from a glance it looks like this command may be needed in your hosting environment:

cd sites/all/modules/civicrm/sql
sed -i '1i\SET SESSION auto_increment_increment=1;\nSET SESSION auto_increment_offset=1;' *.mysql