Hi,

Some functions might or might not be available depending on the context. First of all, you will need to have an image loaded for most functions to be active. I know, this sounds kind of obvious, but I have to mention it. Also, certain functions will not be available if there's e.g. still an open area selection that hasn't been closed yet or if the parameter panel for another function is still open and hasn't been applied yet. If you don't seem to get on with this, it might be a good idea to post a screen shot of the problem situation. That would probably be conclusive as to why some functions cannot be activated and what you need to do in order to get into the right mode again.