You are using way too many Value property nodes. You are bound to have some race conditions, which is probably what is causing your problem. You have wires going through objects making it hard to read your code. Consider using wires instead of property nodes. Also, property nodes are much slower. See if you can simplify your code by putting some of the basic functions inside subvi's and then calling the subvi's from a main program. The way your code is now, it would be a nightmare to find a problem.