estherau; Are you perchance doing multiple clothing items that overlap? If so, you have to do them in an 'inside-out' order (the innermost layer of them all first, then the cloth layer that overlaps that one, then the next, etc), and you have to be -certain- you have added the clothing props into the list of collision items; that last step =will= bring a simulation to a screeching halt with a collision violation. Mesh density can do this as well; either by being too dense, or by being of a different density than another cloth object; you get into the issue that exists with hands and feet. The high polycount of the fingers and toes makes it very easy for a digit to interpenetrate a cloth polygon before collision occurs, and depending on -how- the collision occurs, you either get a collision violation, or the digit is stuck in the cloth and can pull it free of the figure...or teartangle further and bring things to a halt. You might also want to move the animation slider to the frame it halted at, go into the cloth room, and check around the waist to see if there is any interpenetration.