I really havent had much time to work on my 8052 core design recently, other demands on my time mean that its on a back burner at the moment.
But I have come to the conclusion that a processor core in an FPGA is really only useful if you are doing it for reasons other than pure speed. There are valid reasons for processor cores in FPGAs such as being small, secure and easily customisable but I really wouldnt recomment doing it to try to outperform custom built processor running at 100 Mhz or more because you are never going to win.
My most recent experiance was with a replacement for a pic plus large amounts of random logic, we ditched the pic stuck all the logic in an altera acex device which is not a bga package which is always a good thang and implemented a very simple replacement for the pic with a very cut down 8051 core with no timers,uarts etc.
I dont know whats come over me recently Ive become quite an AVR convert( eeek!!!!) mainly because I like the tool chain for avr-gcc.