I am getting slots in the corners where two layers meet to form an angle…

The simple fix to this is that you need to have the layer underneath sufficient enough in strength to support the hot stuff going on top of it. If you have a flat plane that is paper thin, and especially if there is insufficient support underneath, you may find that the layer on top can break that surface, not as noticeably when stacking right on top of the next layer, but more so when covering a thin “shell”. Go into your Craftware in the Slice Basic settings and set your outer shell layer thicker.