Custom poller icon color change in Maps

I'm throwing this question out in case I've gotten way too far into this rabbit hole to think of alternatives (entirely possible).

Here's what we're trying to do:  Create a map with UPS and A/C units status, along with poller status for Battery Remaining, Temperature, Humidity, etc.  I see that you can do this by pulling Custom Pollers onto the map and using ${CurrentValue}. So far so good.

     The problem arises in that the icon color for the custom poller item never changes. How can I get this so that the color will change when (for example) the UPS goes below 20% capacity or down to 60 minutes available?

Thanks for any suggestions!