Adding error handling to parsing of LOAD/BRE/BRNE instructions, which prevent the loading of the assembly file and flag up a specific error the the user.
Important to note that SwingWorker thread's cancel() method causes an interrupt, which if swallowed by a catch block, doesn't actually terminate execution. This means that the thread continues, but with null and meaningless values as registers etc have been reset prior to calling cancel(). This explains the odd behaviour in some cases when trying to reset/restart program execution. In the interrupt handling block of a wait() statment, measures must be taken to prevent any further execution in the event of an interrupt.