I have tried multiple ways to accomplish this so that the groove of this die releases the part perpendicularly to plane #3.
As the die is shown you can see the die cavity wraps around or hooks back on itself not allowing the part to be released. I've tried twisting the profile along the path but that only makes the parting surfaces become non-tangent to one another which cannot be machined.
I've tried making a mold cavity but I cannot make a part that has a smooth tangent face.
I've tried rotated cutout for just the radius portion but that seems to make it even worse.
I have made designs like this many times with other 3D cad wireframe and solid software an this is the first time I have tried this with Solid Works.
I don't normally build them like this. Normally I would start like a machinist with a solid and cut the groove out of it but in trying everything this was my latest effort. I normally don't use the mold cavity tools either as they were never before available in other software but I've never had this difficulty before either.