Hi Keith, I can't really tell to much from your picture, it's pretty small and blurry.
But it does appear that you're using the Kontakt VSTi track as both midi input and audio output. I know there are those that do it that way, however, I not only think it can create problems, but it can also cut down on your options.
I don't know if I'm totally different than others or not, but I put all my midi tracks in the TCP and all my Kontakt VSTi tracks in the MCP along with it's outputs. Here's a shot of a project I've working on today. You can see my midi tracks up in the TCP and all my Kontakt VSTi and outputs in the MCP. I know it's ugly but I don't really care how it looks, it's how it performs for me that's important, as least to me.
As to why your bass track isn't playing, I'm not sure, what controllers are assigned to it in Kontakt? What I'd do is open kontakt and play the track.
Check to make sure the slider for the main volume is up at least to -12 or -6dB (I usually keep mine around 0.0dB depending on the instrument).
Do the main meters indicate there is a signal coming out? If they do, then that indicates a routing problem in Reaper.
If they don't, then it indicates a possible CC controller issue. For example, if CC11 is assigned to the "Amplifier" in the bass instrument, then perhaps it needs a CC11 placed at the front of your bass midi track. Or it could be another controller, Check the manual to see what controllers if any, are used.