The Bkool Pro does not have a proper power meter. It calculates power from speed, so when descending the resistance goes low, you can pedal faster in a bigger gear, it thinks you are making alot of power, the same applies on the flat, get up to a quick speed and power figure ramps up, faster you go. Keep it going over little bumps and before the resistance has kicked you have powered over the bump with silly watts and speed.
I could use a 53*11 gearing at over 100rpm on a flat course for an hour and average of 400W on the bkool sim. I cant get anywhere near that on Zwift and my watts are nearly 100 less than bkool.
The Blue figures are Bkool's attempt to calculate a speed figure when it cant correctly work out one. Once the numbers turn blue, there is no point in putting anymore effort as the simulator has taken over. You can break the blue numbers and get back into normal simulaton but requires an awful lot of speed and effort.