Thanks for the suggestions, I'm checking them out.
As a side issue, I have a very troublesome professionally made, 20 year old control board, which has caused me endless problems (the manufacturer can't offer support). Can I use any of these programs to create a schematic of the traces and components of this board, to try and work out how the board works. I have found that there are some ICs on the board that aren't in the library of these programs. How do I get around that? The part numbers are visible. Thanks.