I don't think there will be issues with release, they have announce that they are inviting hackers and developers to try to hack the platform for a big bounty this is to insure that the platform once released will run smoothly, once the new version is released, Ethereum will have another all time high and will strengthen their position in the market.
We cant tell that. Yes they invited all to try out for some flaws and make it as bounty but sometime there are bugs and error that likely found late. But I am confident with ethereum team that they fan sort out and bugs will not be a hindrance to their new all time high when they launch 2.0. I think Vitalik knows that this will happened so they are ready for every problem. Too bad that I only have few eth on my wallet but hoping can get some from campaigns so my portfolio would grow a bit.