Is Crystal Reports Designer and Crystal Reports for Visual Studio compatible with TLS 1.x+ Note: Due to recent Security and Compliance updates TLS 1.0 may be required to be disabled. NET assemblies as they were only designed to integrate with Visual Studio, etc.). We are using Crystal Reports Designer and Crystal Reports for. You may need to jump through some hoops to get the Crystal assemblies in place (requiring Visual Studio, a separate download of the Crystal.
If you were displaying reports within your ABL application using the Crystal ActiveX Viewer control then you would need to replace this code with code that references Crystal's. Of course, support for this will become sketchier as time goes by and operating systems change. No guarantee that it will be here or working tomorrow. After much searching I finally found this page which looks promising.
Update on Oct 10, 2015: Service Pack downloads for Crystal Reports are virtually impossible to find.
If you are not displaying Crystal reports in your ABL application and only export or print them then you could theoretically continue to use the Crystal XI RDC runtime (which would normally be installed separately). Here is another list of the detailed build numbers for Crystal 20 on the SAP site. If you are not integrating Crystal with your ABL application then there should no barrier to upgrading to CR2013 (but it sounds like this is not the case). As Garry mentioned, the COM-based RDC was removed from Crystal Reports 2008 onward and there is no direct replacement so it comes down to how you were using Crystal Reports.