I don't use Cedega (and probably never will), but for a definitive answer your best bet is probably contacting someone at Transgaming directly, although perhaps someone at Linspire might have an answer as well.
Looking at the Transgaming site, they have a Debian version of Cedega available, which should be compatible with Linspire. If I was in your situation, I would try installing that first. Transgaming states that Cedega will run on Linspire, and if they say it on their site, there should be a way to get it from them without going through Linspire's CNR warehouse. (A guess on my part.)
If those ideas do not work, you can always consider purchasing it through CNR. I recall reading somewhere that doing so will either create a new account or add a year to the subscription of anyone who already has an account. Still, I would confirm that by contacting Linspire first. Good luck in any case.
