can I use different computers when palying the same game, e.g.,

playing live chess with someone or a tournament?

You will need to explain in more detail, exactly what you mean by that question.

For example, I am playing live chess in my office and woul like to continue the game at home...

It is certainly okay for online games (turn-based chess i.e. 3 days per move) but have no idea if this will work for Live Chess. Why not finish the Live Chess game before you change locations? seems logical.

p.s. Thought some more..... unless you live within two minutes of work it can't work. If you disconnect then don't reconnect within two minutes (I think), you lose.

If you don't disconnect, then travel home, I doubt you will be able to log in.... you are already logged in at work.

That's my guess.