Millisecond Forums

Hi,
I have been having some grief with my html instructions (and debrief).
To get them to display I used ./ (otherwise I was just getting a window with no error message, and no html content). Now some of my (online) participants get an error:

but I (and some other participants) don't?! E.g.,
This is true for both (essentially identical) scripts: /gnatsona.web and /gnatsona.web which only differ in how participants arrive (e.g., sona - quatrics - millisecond or facebook - qualtrics - millisecond.

Any assistance would be greatly appreciated!

Kind regards, Leah