How can we add a VF Page in SKUID?

Nikita,

Salesforce puts custom pages into their own namespace.  Try changing the URL of your iframe to->

src=“c__PerfiosAccountOverview?id={{{Id}}}”

Note that you can also add this parameter to the URL to hide the header/sidebar->  &isdtp=vw

src=“c__PerfiosAccountOverview?id={{{Id}}}isdtp=vw”

Thanks,

Bill