ReZpawner

Check the drag of the rocket. I had a few of them flip due to what I can only assume is a bug with the aerodynamics\drag. If that's the problem, then go slow straight up until you're at above 20k before turning.

Solved it! If you have problems installing Kerbal Engineer, more specifically, you get greyed out items that says that you need to research them before use (which of course you have), it's because you have the old files in the Kerbal Space Program folder. From 0.21, it was in <game directory>/parts/<parts directory>. If you edit the config files here, adding the lines mentioned by other posters ( TechRequired = start entryCost = 0 ), and save the config files, you will once again be able to place them. You're welcome

Did anyone figure out the problem with greyed out parts yet? It seems like quite a few people have this problem. Starting a new game does nothing to solve it, nor does editing the techs so far.