Sorry for the delay, I was away for the last week.
Please send me any projects which crash so I can investigate them. I can often recover projects to stop them crashing as well. Please report issues like this as bugs and read how to report bugs - you *must* provide all the information mentioned for us to be able to help, otherwise we cannot do anything.
If you have too many tabs open, deleting all the .uistate.xml files in the project will reset the UI to default and open the project with no tabs open, or one tab open (I forget what it does in that case). If you have a .capx project, rename it .zip and extract it to get the folder project.