Regarding using "libraries created by other members", the CC license states that the following condition is met:
Attribution — You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).
It seems that the onus is on the developer to specify any such requirements, and it would seem logical that for clarity, any such requirements should be specified in the original post in which the library is shared.
For my part the libraries I have created, although trivial in workload compared to some from other users, I have shared so that others can use them, and to add to the overall functionality of B4A.
While it would be nice to know if the libraries are useful, and are used in published applications, asking that the libraries are attributed in developed apps could lead to a long list for some apps, and some could easily be overlooked amongst the 'official' libraries.
Personally I would be happy for a message to be posted in the Library thread that says something like "Thanks for the library, I've used it in xyz app if you want to check it out".
If others do want attributions, you could do it on a splash page, or a separate menu option.
This is my take on it, and applicable to libraries I have generated.