1. No. You can use the same email addy. In fact, to setup the second PC, you can copy everything in the distributed.net folder except the buff-in.xxx and buff-out.xxx files to the second PC and start it up.
2. In the dnetc.ini file, change the following parm to read:
[misc]
project-priority=RC5,OGR,DES=0,CSC=0
Delete the buff-in.ogr and buff-out.ogr files, restart the client, and you should be running RC5.
😀