It looks like your flash detection routine (in flash_detect.js) is to blame. Running it in Chrome, Firefox and Safari returns the value '0'. In IE, it gives the result '8' (even though I have 10.1 installed).
In flash_detect.js, there is a line:
var latestFlashVersion = 8;
Change this value to 10 and all 4 browsers I've tested it on then return the value '10'. This might be enough for your website to function in the browsers mentioned above.
However, it is obviously not a future-proof flash detection routine (as it needs to be told what the latest version is) and you might be better off embedding your galleries with SWFObject which handles flash detection, allows you to specify a minimum Flash version required and supports expressInstall for easy installation of Flash for those users who do not have the minimum required version of Flash installed (see http://simpleviewer.net/simpleviewer/su … ng.html#js for details).
SimpleViewer Support Team