Hi All,
I have just been working with the demo of CorelCAD 2021, and it's a fantastic upgrade over 2020.
2020 I found buggy, as was 2019/2018. Both failed to work correctly with AUTOLISP and both had issues, though some improvements over 2017 were still present.
On the other hand, 2021 not only works with my earlier thread-making routines, it addresses the bugs present from CorelCAD 2012 to CorelCAD 2017 that required manual intervention and now just flows through the options, although it still takes a long time.
So far I have noted greater speeds and performance in 2021, but the big thing....
STL import/editing.
If you're in it for 3D editing, then this is the application. It does bring in a STL file, so doesn't have the resolution you expect from a CAD file, but you can work the incoming STL as though it's a full solid.
If the STL is damaged ( eg, open surfaces ) then you have to repair it first, which you can do with meshmixer, otherwise it comes in as a series of surfaces which don't allow 3D editing, and presently there seems no way to manually fix the mesh with CorelCAD 2021.
Outside of that, fewer crashes working with large files, and faster operations seemed to be the case, but I have not measured them you, so it might just be my imagination. Also, it seemed to work better on putting nodes up to lock onto than 2019/2020.
If you're working with an earlier version, 2021 is definitely the one to download and try.
David.