One of the issue surrounding the porting of Windows-based CAD to Linux is, How much of Windows comes along? — OLE, COM, and VBA, in particular.
On the Bricscad Linux forum, Luc De Batselier answers the question, "Which APIs can you expect to be available on our first Linux release?"
LISP and DCL are supported. Even though vla-, vlax- and vlr- functions depend on COM, Bricsys has figured out how to implement them COM-free on Linux.
SDS and ADS are supported, except for Windows-specific SDS function.
BRX and ARX are not supported in the first release, due to the number of header declarations tied to Windows, and the number of existing third-party apps tied to MFC. BRX may be added to a future release of Bricscad Linux, if there is demand.
COM and VBA are not supported, by design, since they are specific to Microsoft.
In the future, Windows-specific functions might be ported to WxWidgets, but no decision has been made. In any case, BRX development will continue on the Windows version.