Please accept our deepest and sincerest apologies. Note that we did do a beta testing round and several rounds of internal testing before we released v2.0. Unfortunately we just couldn't anticipate all the several various setups that our many thousands of users would be on. Please note, this was a significant update and we made note of this before we released it to the public.
But, what I'd like to point out is that it's actually working well for a large percentage of users. We know this from feedback and from the fact that a lot of people are upgrading to Pro, which they can't do if 2.0 isn't working well for them. However, as you have seen from experience, there are issues for some users.
Keep in mind that NextGEN is active on 550,000 websites. So if a small percentage have problems, that's still a big number. And the ones we hear from the fastest are precisely those with the issues. For those users, like yourself, the best thing we can do is rapidly troubleshoot and push out the next release. We'll be introducing a couple dozen fixes in the next couple days, all within a week of launch.
What we've done here with v2.0 is rare. NextGEN is a very old plugin. Because it's been around a while, it's deeply integrated into the WP ecosystem. Many people have customized it. Many plugins integrate with it.
We've basically given NextGEN it's first full revamp/rework since it was originally launched nearly 6 years ago. Most updates that Alex did, and that we've done since we took over last year have been minor. This last one was massive - a total overhaul.
Because NextGEN touches so many things, that kind of massive overhaul is just bound to cause some issues.
We did a ton of internal testing, and also pushed out a public beta for a full month. We had over 1000 people download the beta and we got a lot of feedback. So we tested thoroughly.
But there are just bound to be issues, and now it's just our job to resolve those as quickly as possible.
If you have found and confirmed a bug or incompatibility issue with v2.0 on your site, please send as much detail (login credentials would be incredibly useful for our developers) to http://www.nextgen-gallery.com/report-bug. Or, you're welcome to try our latest beta here: http://www.nextgen-gallery.com/nextgen-gallery-latest-beta/ or rollback until we release our next update: http://www.nextgen-gallery.com/how-to-rollback-a-version/
Again, we're very sorry for the inconvenience these errors have caused, we'll do our very best to produce a solution as quickly as we can.