There is currently only one known bug, and it is that the program cause illegal operation, usually when there was a lot of output, like after some time when training it from start structure. This bug occurs when calling a dll function, and it is a question whether it is indeed a bug, or an operating system fault. This bug can be overcome by saving the structure before the bug occurs, starting the program again, and loading the saved structure, and a training program. At present, this bug was tested only on windows 2000 operating system.
Fixed on 2004/10/01 by Tarvo Korrovits -- mistakenly WINAPI was declared as a calling convention of dll functions, while in dll the calling convention was standard C; this resulted in stack overwlow when these functions were called many times, though the code otherwise worked correctly.