My problem is this; When I look at my photos in my library they are beautiful but when I arrive in the development module to modify them, they become full of red pixels in the sky and blue one everywhere.
The problem is difficult to describe in word, so here are two screenshots for the same photo in first library mode and the second one is in the development mode (with the bug)
You're seeing the shadow clipping display.
Switch to Develop module. On histogram (top right of screen) click on the the two triangles (top right and left of histogram) to switch off the clipping display
It's not a bug, but rather a feature. The blue that shows up is indicating that your shadows are clipped. In other words, you are losing detail in the shadows. The red is indicating that your highlights are clipped, which means you are losing detail in the highlights. You can use the develop adjustment tools to help alleviate that problem. Or, if you don't want to see those indicators do you need to hit the J key to turn them off or click on the little squares in the upper corners of the Histogram to toggle the indicators on/off.