OK I see, so when you said "for which the best known solution does not save 100%", I guess what you meant was "for which my best known solution...".
No; what I meant was "the best-known solution"; that should teach me to be careful about punctuation even on forums! In other words, the best-known solution to the level, not specifically the best known solution to the problem of saving as many as possible.
Anyway, that was just a starting point; LemSteven's list obviously supersedes this, except that he needs to tell us which solutions depend on bugs and what the best solution is that is guaranteed on any version. In particular, are there any solutions where 100% is only possible because of a bug?