Hi Mel,
Chiming in a little late as usual. I run a biesse rover 30. No 3d or 2.5d just closet parts. Several posters hinted at this but I just wanted to reinforce it. There are 2 different types of programing for use with the CNC.
CAD and CAM, Auto cad is for design and sounds great but you will also need a compatible CAM software to generate G code. There is also just G code programing, This can be done in text or with the help of an editor like Biesse works. Mine predates Biesse Works but has an editor that help write g gode.
CAD - Computer aided DESIGN
needs to interface with
CAM - Computer Aided MANUFACTURING - generates g code to run the machine.
All g code is not the exactly the same so CAM programs have "post processors" or posts for different machines, Think of them like printer drivers.
Or you can get down and dirty and write g code. (I love this part)
One rule of thumb I think you already know - the more powerful the software the harder it will be to learn.
Just reread and one poster said AutoCad can generate G code. That would make it CAD-CAM. Other programs like Aspire are CAD-CAM or what is referred to as Screen to machine. Just make sure before you invest a lot of time to make sure your strategy covers both elements so you don't have any surprises after a large investment in time.
I am of the mind set that with the internet any determined average person can learn almost any skill. With the help of forums like this for someone like you AutoCad ,,, no worries, You probably have the basics covered already!
Sorry if this is just a rehash of past posts,