Having been through the patent process, your ideas have to be documented as originating with you and well documented in a patent application before you can even submit the idea for a patent. That said, even if you have a patent, you have to be prepared to identify anyone using your idea and implementing your concept with legal action. Basically if you are not willing to defend your patent, it does not protect you at all. That is why the Chinese copy any good idea and put out copies with minor modifications on the market, usually before you can even get your own product out for sale. So you need a really good killer application to make it worth the effort for a patent and its defense.
Correct, and Farnell and the element14 Community do not position themselves that there is any agreement, arrangement or otherwise at the time of writing.
Further, pay attention to the "Terms of Use" and "Legal and Copyright Notices" in the footer of the page.
I wouldn't worry about ideas. Ideas are not patentable.
For concepts: contact a patent law lawyer, and ask what your options are, once you made a design public. There is no specific arrangement for this forum.
Some Countries do offer limited time-period after public disclosure but they are heavily Jurisdiction and situation dependent. So keeping it simple. If you disclose before you file a provisional patent - YOU DO NOT GET ANY PROTECTION, IN-FACT, YOU CANNOT FILE A PATENT
Update: Ideas that essentially are detailed enough to explain construction of the invention are sort of patent-able. But Otherwise general, vague and abstract ideas are not patent-able
