No, it's not a glitch (software bug). The issue is the speed at which events (such as collisions) can be calculated. Inside Algodoo there is a clock called "simulation frequency" that determines how quickly physical simulations are calculated. If that clock is set too slow, then fast moving objects will not collide with each other, such as what you experience in this scene. If the clock is set too high, collisions will occur (even very fast ones) but most slow, and even some average speed computers will lag. The default speed for the sim frequency is 60 Hz which is a little slow but most computers can handle it. As an experiment, I set the sim frequency to its highest number (1200 Hz) and then the little fast moving cannon balls collided with the target every time. If you want to try it yourself, click on the little white gear in the upper left corner next to "file", then click on "simulation".
