SAP discontinued the CR 8.5 trial long ago, but if you find an ISO of "Crystal Reports 8.5 Developer Edition" (abandonware), you can install it on a virtual machine to . The runtime files can then be extracted.

If you only have the OCX and DLL files (manual method):

If you are looking for a reliable way to get this environment working today, this guide covers the legal availability, installation steps, and integration methods for your project. The Reality of "Free Downloads"