Orange Mobile Broadband 515m Dongle Not Working With Windows 7

I run Windows 7 64bit os with an Orange high Speed (!) mobile broadband dongle (515m). The software (Internet Everywhere) stopped working months ago and after much arguing with Orange, they admitted that it was a software compatibility problem with my os but promised that an update would be coming soon. They gave a workaround which meant the dongle worked on dial up (with associated speed). However, after waiting months for the update, it's finally arrived but it still doesn't work! Just like the last software version, after installing it clean, it crashes at start up and won't operate. Last night I had to stay up hours to roll back my system to get the dial up working again as it prevented that from working too. I'm really sick of this and Orange's response has been woefully unsatisfactory, bordering on insulting. The latest gem was to uninstall everything internet connected then download the software! How? This has been pretty much the level of response from Orange. I'm about ready to cancel my contract with them for breach of contract.

Oh, my laptop is an Acer Aspire 7540.