Use the Rectangle Drawing tool option to specify your inverted (internal) corners. (see screenshot showing corner types you can select from)
Not exactly sure what you mean for "outside to angled", but I'll make a guess you just want a chamfered (angled) edge cut around the perimeter. If so, you can use a V-Bit profiled along, or offset from, a perimeter vector. Either create an offset vector from your perimeter cutout vector or just offset the bit when creating the profile toolpath - of course the amount of the offset will depend upon the bit angle and the depth of cut needed for how much of a chamfer you want. There is another way to do it with Pocket v-carving, but the Profile method should do nicely. Your choice.
-ShopBot Buddy PRSAlpha CNC