Proxima Polyhedron

Would love for there to just be the option to change keybinds manually. The Alt key being bound to this drawing mode isn't much better than Ctrl, as I now have to remember to tap it after every time I Alt+tab to another window. Letting users adjust these keys themselves would be a lot more efficient than changing hardcoded keybinds every time a problem like this comes up.

I am forced to use an old version of Paint.Net because I am working on a Windows XP machine. I know that support for this version is long dead, and as such am not expecting support, but I am nonetheless sending this out with the hope that someone can help me. I have Paint.Net 3.5.11 installed, and the Curve/Line tool is defaulted to the Spline setting, without any option to change to Bezier curves. As someone who works with lines that need to curve very smoothly with no "angles," the Bezier setting is vital to my work. Is there a way to change this setting? Can I use a keyboard shortcut for it? Is there a menu setting I am not seeing? The changelog says that Bezier curves were introduced in 2.5, so I do not see why this version should not have it. Clearly this is an error on my end but I feel I have exhausted the options for how I am handling the program wrong. Any help is appreciated, -Proxima Polyhedron