Gameux.dll is a Microsoft file probably linked to DirectX. My simple problem is that FSX has been decapitated because I had it installed on my secondary drive which went off to see its maker! Now, when I try to uninstall or repair FSX it can't find the body of the program I suppose, and comes up with seemingly spurious reasons for that. Trying to uninstall all mention of FSX from my C: drive is likely to meet with failure. If it was that simple none of those naughty paedophiles would be damned by evidence from a computer they'd imagined they'd cleaned!
As for registry cleaners, Microsoft's view is that they are all smoke and mirrors, for an unlinked entry in the registry does no harm but take up space - so I'm told. What I have not been told yet by these wizards is how to fix my problem. No-one would believe the number of sure-fire fixes I've found in other forums and which have all done nothing for me.
One thing I have found is that most downloads of free software come with many unwanted applications that install themselves whether you agree or decline and simply deleteing them in control panel is not always immediately 100% effective. Worse still, those downloads you have to accept from adobe for their FlashPlayer always come with unwanted apps which though free on the face of it can cause problems which seem to need a bought app to remove them!
Fozzer ... even the mightiest of the God's must fall, ask my mate Jupiter!