The bolt should be a separate jointed part. You will have to go into the "joint editor" and set both thr bolt and the door to "do not bend". Or, go into the CR2 file with a text editor and put a star before the first letter in the title line of all "paragraphs" that describe "joint" and "twist" and "smoothScale" type channels of the joint between the bolt and the door, that star tells Poser to ignore those channels.