CADKEY users state that v20 products are slower than prior releases and unusable, missing many of the key routines that failed to update from prior versions.
Customization of CADKEY is at a standstill as the company has yet to implement end user compatible CADL routines. The company is also supposed to be working on a CADL converter for update of the many libraries of customized functions that exist within each user company but, just as the application is unable to properly support the update of old routines, so is it unable to provide updates.
The company chose not to include any backward compatibility paths for PRT, PTN or CDL files. There is no Save As that will create these files as compatible with earlier CADKEY versions. If you chose to adopt CK20, which few users have, your designs stand alone and can't be shared readily with earlier version users.
The solution for export is supposed to be IGES which has restored support for solids but neither CK99 nor CK19 did. Also, IGES export from CK20 to IGES import to earlier CK versions has a host of other incompatibilities including text and dimension mishandling and no usable support for Layouts. In short, you'll spend a great deal of time across several file formats to find a mix that will export solids, surfaces, wireframe and detailing. Any use of OLE will be lost. Any associative features between models and views or detailing will be lost. If CADKEY exports improve this may strengthen the link to other CAD platforms but provides no solution for earlier product users as there is no intention to provide import improvements for any of these products. CADKEY Corporations own developers have indicated their ignorance of these problems and their product by suggesting that the added ability to export wireframe in CK20 SAT files is the solution for sharing data with older versions. THE OLDER VERSIONS ONLY SUPPORT SOLIDS FROM SAT FILES AND CAN'T OPEN FILES FROM NEWER SAT VERSIONS!
If your current CADKEY version is getting the job done it will likely be two or more years before the newest generation will gel and provide a workable incentive for update. If you current CADKEY is not up to task then the latest generation is worse still and provides no solutions. Batch convert wireframe and detailing to DXF, export solids as SAT, STEP or Parasolid, export surfaces as IGES and find an application that'll recycle this data and provide the tools you do need.