ActiveX Settings, Security Settings

I have an ActiveX control in one of my PowerPoint presentation, and I
want to
enable it, but I go into Trust Center, into ActiveX Settings, but it's
all
greyed out, I can't change any of the settings. I have macros enabled.

Any ideas on how to make my ActiveX controls work with PowerPoint on
my
computer?

Is there some registry settings I can change?
Do I have to get the ActiveX controls signed?

Also when I go into other presentations while in Slide Show mode, when
I
close them it asked me about saving the shows, any idea how to get rid
of
that?

One other thing, is if there's a web link on an image, it will prompt
a
security warning about the image, I'm looking to get rid of it too.

Thanks