There will be two posts minimum...
First, I'll refer you to the Knowledgebase Articles that give the needed information, and second I'll give you code samples to run a report given the methods I use. Specifically, I access a SQL or Access database via ODBC, but either database will work with the code samples.
This basic document is a good place to start.
The biggest changes were the new ConnectionProperties in version 9.0 and later.
They are explained in the following document:
The RDC code is described in:
If you will be running reports from older versions of crystal, I recommend using the property .DeleteAll and add the new properties in for ODBC. Each connection does have different properties as it now reads the driver; ODBC, OLEDB or Native.
The information is there, but I did not find these articles particularly user friendly.