I've already downloaded DOS2 at GOG. Apparently I either crowdfunded or paid for an early purchase because Linux was mentioned as a supported platform. I can't run this download. A few people seem to have success getting it to work in Linux, but unfortunately I'm with the crowd that can't.
Which is "okay", since you clearly stated that Linux wouldn't be available at release.
But...
1) I just wanted to inform you early that next time, I'm not paying anything until a playable version is on the proverbial table. Unlike other games, I find the delay this time to be psychologically unpleasant. I want to play. Now.

So don't count on crowdfunded money from me to subsidize creation for
other people. Fair warning.
2) Be sure to deduct 1 from your count of "Windows copies sold". I already paid, and I already downloaded, but I can't actually play. I'm waiting for a Linux version. Next time, you'll more easily have accurate bean counters, but this time I thought you should know that your counters are wrong. Please deduct 1 from your Windows counter, and increment 1 to your future Linux counter. Accurate data is important for prioritization. You already have my money, so it might be tempting to continue delaying the Linux release. Please don't succumb to that temptation.