Algodoo

Well I'm not Xray but I can explain this.

Ropes are weird in this game, they can always glitch away, try using a box instead

Yeah, I messed around with it and saw the ropes glitch the box away.

So if you're using ropes for something, that might not be the best idea.

Before running the scene, click on the rope (right click to bring up the Edit list) and all 35 segments of the rope should be highlighted. Then click on Script Menu. In the Script Menu you will see something labeled "Bend Constant" and it will have a value of "NaN". Click on "NaN" and change it to any number (such as 10). At that point you can back out of the Edit Menu and run the scene. The rope will no longer glitch out.

The problem is that some values, such as Bend Constant will default to NaN which means "Not A Number". Because it is not a number, the software does not know what to do with it, and so it goes crazy.

I also noticed that your chain and the box above it are extremely light (they have very little mass) which could cause problems. You could click on those things and increase the mass slider. They will then behave properly in an environment with gravity.

Hope this helps!

THE ROPE desity is 2, and strength is 0, but its making its own energy

You did not make the changes I suggested. That's why it is still doing weird things. If you would follow my instructions instead of randomly changing things, the rope will settle down and stop acting crazy. Now, will you make those changes, or do you want to keep posting weird scenes and asking people WHY is it acting crazy?