Contact Import: One of parameters (value: Array) is not of the type Integer

Unable to import contacts into Existing or Newly created Group(s), received the following error:

One of parameters (value: Array) is not of the type Integer

To reproduce the error:
Using the Import Contacts UI wizard, going through the basic process. When selecting a Group in the Preview stage (either an existing one or creating a new) and then running the import.

I was able to reproduce this on: http://d44.demo.civicrm.org/

I have attached a sample CSV I was using, which is just a small selection of the original sample data from the test site..