I've asked a question on the Chemistry Stack Exchange and my language was not clear enough. So it was put on hold because it looked like a question for Biology SE. Then I've asked the same question on the Biology SE, as advised. Then someone answered my question, because he understood that my language was unclear but the question was good for Chemistry SE. But then the question was closed for cross-posting. Then I changed the question so now it's clear that it's good for the Chemistry SE. Then I even deleted the question on the Biology SE. So now the question is valid but how can I ask for reopening it? I only have 11 reputation so I don't have the "vote re-open" button available.
And since everybody forgot about that question, now it can't be re-opened.
I think there should be a mechanism accessible for the people with low reputation in order to allow them to show to the community that they solved the problems with their closed questions.
And I think there should no be time limitations for such things (like: "if you re-write the question in X days then.."). Once the question becomes valid, the users should be able to ask for re-opening it.
The user "Dr. Wily's Apprentice" expressed such an opinion very well in this answer.