QTH.COM Swap Chat

I have a ic-756 proII that the main processor is bad. My problem is that Icom not longer sells the processor for that radio. I was also told that Icom puts a down load into the rom on that chip so getting one somewhere else will not work. If this is all true how do I get the needed part or the download that makes this work in a ic-756 proII.

Norm W1FIF