thanks for getting back to me and sorry I wasn't able to reply yesterday.
I didn't mention, but the inability to add the tool to those charts was when the charts were linked to a spreadbetting account (and have _SB added to the symbol) so I don't know if that could have been a factor because after my last post, I was able to add the tool to the same symbols when linked to a normal account.
With regard to the 'Missing Parameter' issue, when I opened a chart for US500 yesterday, the box appeared but when I followed your instructions, the info was accepted and the box closed, so I'd probably entered the wrong details last time.
Just a couple of further questions before I purchase as trial has ended now:
I noticed that with multiple tabs, if the Trade Server is running in one tab it connects to the Risk Reward tool in another tab. Is this behaviour ok and if so, is it necessary to have the Trade Server displayed on each chart?
Finally, is it not possible to set the defaults for the tool, otherwise the parameters need to be entered each time the tool is added to a chart. Also, there doesn't appear to be a way of saving any changes to the colour/lines of the boxes.
Many thanks for your help