TN3 WP Plugin, Gantry framework and cross-platform Gecko browser issue non-displaying pages

Hi, Found a very obscure problem - using TN3 plugin version Lite in WP 3.4.2 with Gantry Framework 1.31 and Rocket Template Modulus, pages with TN3 display NEVER finish loading (therefore never display) on cross-platform Gecko based browsers (Firefox and SeaMonkey). Appears to be in new versions of Firefox, etc. as it works fine in Firefox 3.6.24 on Mac and Firefox 13.0.1 on PC. Works fine on Camino (Mac only and Gecko-based), Opera, Safari, Chrome. Even IE8 works fine!!! Anyone got any ideas??