Is this site suitable for asking questions about problems found on an implementation of an algorithm in a library or this types of questions should be asked on StackOverflow.
Here is what I would suggest. If you think the problem lies in the implementation, StackOverflow is probably the better place to ask. If you think your problem lies in a misunderstanding of some cryptographic primitive or concept, try to boil your example down to that specific cryptographic primitive or concept and ask about it. On our site, some pseudocode is fine, but the more code there is the more likely it is your question will get put on hold.
Worst case scenario you ask on one site, figure out it should have been on a different, and flag the question to have a moderator to move it. If you do post on StackOverflow, I suggest you add a comment on your meta post so we can follow it.