The system has worked perfectly from the programming and electrical point of view. There have been a few failures in the mechanical engineering, mainly with the rubber bands I use for the pulleys, and the pulleys coming loose.

In general the big advantage I find for documentation for open source / Free Software projects, is that it usually states both what the software can do and what it can't do. As opposed to proprietary software documentation which usually has a good dose of marketing speak, and the only way to find the limitations is to search the documentation looking for a feature or a way to do something, and not being able to find it; then you realise the software can't do that!