How to seal Delta shower valve ?

I just installed a Delta single-handle shower valve in an acrylic shower enclosure and I'm wondering how to seal up around the cover plate.

No matter how I adjust the plate, there is a small gap in the seal on the plate around the valve handle area. There is a foam ring on the cover plate, but it seems far from adequate to actually seal around the valve. Water bouncing off a body will almost certainly find it's way past this. Is this an area best left to silicone caulk ?

Also, should I run a bead of caulk around the outer rim of the cover plate ?

Thanks,
Charlie

The provided foam rings are generally adequate. You can caulk if you wish, but try to achieve the smallest possible visible bead, because caulk inevitably becomes a maintenance issue.

I've never had any call back issues with those foam gasket backed cover plates...I don't use any caulk.