>1. Are there any differences between VFP 7.0 and 8.0 regarding Database Events?

Not that I'm aware of.

>2. Do database events execute properly even when VFP is not present? For example: let's say a VFP app is installed on a network and the DBC uses database events. A user has a workstation on the network but the app is not installed on that workstation and the VFP runtime is not installed. If this user attempts to access a DBC (for example, by importing from some other database or via ODBC), will the code in the database events execute? Will all of it execute or only some of it?
> I want to use the DBC_OpenData event to prohibit unauthorized use of the DBC, but if a user attempts to open the DBC in an environment that does not support VFP, does the VFP code in the event execute? If so, does all VFP code execute or only some subset?

A database with DBC events cannot be accessed through ODBC because ODBC doesn't support DBC events. Only VFP OLE DB provider can be used to access such DBC.
Using DBC events is very weak protection because it can be easily circumvented.