Photos can view different libraries just by dragging the library onto the icon (or using the option key).
However, RAW Power can only open the System Photo Library.
The first thing to check is whether the library you are viewing in Photos is actually the System Photo Library.
To do that, go to Preferences in Photos. Click the System Photo Library which will change that setting.
After doing that, quit and reopen RAW Power.
Changing the system photo library can affect how iCloud Photos works. I have a video on the YouTube channel which explains this. (YouTube.com/gentlemencoders)