I was working on a model and saved the model before I attempted to make changes to the design. I made changes to my base feature and had some fillets fail. (not sure why all the fillets failed in this set but they were missing). I cancelled the edit on the fillet and then watched as my model progressed backwards doing an Undo type function, past my last point of saving and then ended with a model that still needs to be rebuilt as the sketch doesn't represent the model being shown on the screen.
Fortunately, my save point was left unscathed so my file is at a state that I can work with. But I did notice that when reopened the part and made the same change that SW crashed. This can be duplicated by moving the top connection point so that that two spoke cross-section pass through each other. I expected the fillet around the main hub and the spoke to fail. But not the fillets on the spoke arm- which based on history causes the fillet around the hub to fail since its edges don't exist. I tried to keep each set of fillets their own feature so that only specific fillets would fail.