Mailist to discuss all issues regarding the Digitech GSP-2101 Guitar FX Processor

Hello guys,
this is my first day in this group, and I am glad to have found 
people who are sill working with the 2101.
Please don't laugh about my "small- talk- english" because I know- 
I'm not so goo in this language :-)
Ok! Here comes my first question:
But before I could tell it, I have to explain someting:
I have got two 2101, the first is a Nov'96 - Version (Artist, SV 
3.00.a , One-EPROM- Version)
the second is a Jul'94- Version (SV 3.00.00.a, Two- EPROM-Version)
I bought it sone month ago. And some month ago I found some 
interesting PPC210- Patches at the Internet, and I wanted to try 
them. So I tried to get a PPC210. But I did'nt, because it's out of 
production. I decidet to build 2 PPC210 by my own.
I have done that already. And they work fine. But there are some 
problems/questions: If I use a S-DISC-II for the PPC210, it only 
works at the Nov'96 - Version (there is a SMD- S-DISC II Processor in 
this GSP2101). At the Jul'94- Version (placed with a S-DISC I) it 
only causes big digital- noises like "chchfrsrchchfstchchfst....." 
added to the sound. If I put in a S-DISC-I- Processor, the PPC210's 
work good in both units. The known "cannon in echoplex- sound" 
appears in both cases. There is no error on my self- made PPC210, 
because with an original PPC210 (hired from a friend) the same effect 
occurs.
Now my questions: 
Does anybody know the differences between S-DISC-I and S-DISC-II?
Can anybody explain, why the S-DISC-I and S-DISC-II (on PPC210) can't 
be combined?
Randy Thorderson explained 
on "http://www.bstage.com/mail_archives/gsp-users/html/gsp-
users.9802/0117.html" that digitech will do a software-tweak to solve 
the cannon- problem. Did digitech really do that tweak?
Thanx for every help,
Dieter