After a little, ok A LOT of investigation, seems it's not Renderosity or my machine causing the problem. 

Seems Google Chrome updated  last night and changed the scroll bar somehow. Removed the arrow boxes and apparently the funtionality of the scroll bars. :(  I'm not the only one screaming foul on this one, there are pages of complaints on the Chrome forum.

I tried adding the Win 7 Scrollbars ext. to google chrome, no joy. So until/if there is a fix, I'll be using the little arrow keys to scroll side to side. I'm so not happy about this.

The new update is being rolled out to everyone this week, Tina if yours still works all I can say is either you haven't gotten it yet or you're much luckier than I am, lol

This is the update version causing the problem for me:

Version 32.0.1700.76 m