That sounds about right, it usually takes longer than you think when you take into account everything that needs to be done. Most projects you see are release about a year or a year and a half after they're first started.
I think there will always be the occasional bug or glitch, it's just somethign that comes along with hacking unfortunately. As long as they're not game breaking glitches, it's easy to just smooth over the smaller bugs if you get any reported. It will happen because I've had plenty of that, but nothing a quick fix can't solve!