error message is still present in Firefox 5 after an "S" hotspot is clicked in the LiveText window.

The EdExcel/Pearson A-level (UK) Core mathematics textbooks e.g. ISBN 978-0-435519-10-0 provide a CD which contains the full text of the book plus some dynamic links scattered through the text which can be clicked to reveal only a question or its full, worked solution. The process of revealling the content is to launch the "LiveText" application held on the CD. This opens a dedicated window with tools to navigate the contents of the electronic book by page number or chapter or section number. At certain points in the ebook , at the start of each exercise, is an "S" button which when pressed launches a browser window to view the required content. Now this was failing in both Firefox 5 and IE 8 with error message "Unable to load C1_ch1.xml" the link in the browser had become file:///D:/content/sb/content/c1_1_d_1.xhtml (for example) a location on the CD. The fix for IE8 was to load "MathPlayer" from http://www.dessci.com/en/products/mathplayer/download.htm after this install and restarting IE8 the process on linking to the CD content by clicking the "S" in the LiveText window operated causes IE8 to show the required content. The problem of the "Unable to load C1_ch1.xml" error message is still present in Firefox 5 after an "S" hotspot is clicked in the LiveText window. This "dynamic link" is very useful to go straight from the text of the ebook to a structured presentation of every question and its solution. Is there some other setting in Firefox 5 that needs to be changed to make this work? Regards Clive Long