It's unlikely that the maintainer takes part in a discussion here. The usual approaches are asking in #qt-creator on FreeNode IRC (preferably during Central European working hours) for short lived "How should X be done?", the Qt Creator mailing list for "important" design discussions/decisions, and codereview.qt-project.org for actual discussion of implementation details. JIRA is of course also ok for things that should not be forgotten. For your particular issue, IRC would probably have been the way to get the quickest response.
The time until someone responds also depends on the severety of the issue, and other circumstances. There's e.g. feature freeze for Creator 3.3 tomorrow, so people are really busy.