JTCS 2.0 Upgrade is this Mandatory ??

[berto]

It should be the case that 2.00 will read 1.04 files, but not vice versa. So, yes, with 2.00, you should be able to read in 1.04 files, no problem. But then they get converted to the new 2.00 standard when saved anew. That is why your opponent needs to have 2.00 to proceed.

Having said that, better safe than sorry? Better to continue playing out your current game(s) with both players remaining on 1.04? I don't want players flaming me if something goes wrong.