Me again! Asking for more advice. I need to repair some areas of plaster in the kids' loft rooms (Victorian house). I think I can deal with the cracks but the part where the wall meets the sloping ceiling is uneven and bumpy and looks like it has been patched up before by the previous owners. I just want to achieve a nice smooth rounded/blended effect. Is there are product and technique that I could use? Is it really difficult? Help! :)