As for downloading the project, no I'm afraid you can't download it and program the CPLD.
The open core is a design that could be implemented in any one of several dozen programmable gate arrays from several manufacturers.
These are the steps you would need to do in summary:
- Download the core and compile the source files (either verilog or vhdl)
- Look at the top level entity definition. It defines the incoming and outgoing signals
- For each signal, map it to a pin on the actual chip you're targeting by filling out a user constraints file
- Pass the RTL files from the compile step and the user constraints file to the fitter. <-- This is the step that will definitely fail when you try it on a CPLD
- Convert the output from the fitter into a series of JTAG commands
- Result: an xsvf that can be loaded into the CPLD
It sounds a lot and it gets easier after a number of projects, but now you know why I provide ready compiled cores for you on the Guzunty website.
Don't let me put you off if you want to have a go. In fact quite the opposite, if you want to have a go I'll bend over backwards to help you out. Hardware design languages are just _so_ cool you'll be so glad you had a go (but I will encourage you to choose a simple example to start with
Guzunty: A fully programmable peripheral you build yourself! https://github.com/Guzunty/Pi/wiki