Issue when setting up parent categories andsub-categories

Hi,
I installed ver. 2.0.0.0 and I tried to to a clean install so I deleted all products and categories in the test version. After setting up a category I tried creating sub categories only to find that the "Parent" line in the admin is not working. I entered the name of the top category... nothing. No autocomplete, option or anything alike.
It keeps creating parent categories.
Any ideas?
Thank you.

A clean install is with a new database, not with an existing one.

Sorry, I meant to say that I tried getting rid of all products and categories in the test version, and deleted them. I then entered Categories menu in admin and started creating my own categories. In previous versions of Opencart there was a drop-down list to select parent category so I assumed that here, if it's missing, there's at least an Autocomplete option.
The database is, of course, new and I created it just as I was completing installation of ver. 2.0.0.0

Just checked but for me it works.

Could it be that it is browser related?

Wow! Right on the money!!
Mozilla's Firefox is having issues with the dropdown. Just tried IE and it worked just fine.
Many thanks.