After a call to the CMC Markets helpdesk I got the CFD trading software running under Vista using XP compatibility mode, and everything seems to be going OK. The wireless network router and USB adapter didn't arrived today, so I don't know how setting that up will work out. Meanwhile though, I'm having problems running both Firefox and Explorer. Firefox freexes up ("not responding") every time I try loading my blog site (although it loads perfectly well using the same version of firefox on my laptop running XP), and on a couple of occasions Explorer has tried to "connect" to the internet when it is launched, even though the internet is already available (as I have the CFD displaying live data in the background).
I'm not sure if the fix will end up being upgraded versions of Firefox and IE, or a fix to Vista. I've also had one "blue screen of death" event, even though only application (the CFD trading app) was running at the time. As I haven't changed anything from the initial configuration of Vista that came with the new PC from Dell, it looks like these problems may be with Vista itself.
Vista looks very pretty, but so far I'm not overwhelmed by the reliability.