I thought .sol files are the saved games? I have no saved games yet and no .sol inside the app package.
A .sol file is created and saves the progress of your game even if no save slots have been used. In other words, you'll be able to click "Resume Game" and you'll play from where you'd left off. But yes, because you haven't used any save slots, your progress would be lost as soon as you click "New Game."
So when you say that you have no .sol file inside the app package, my guess is that you'd checked in the main Machinarium application—where there isn't a .sol file—instead of the Machinarium.app
that is nested within your Library folder. Is that what you'd done, pixelstuff?
My understanding was that a .sol file is created whenever the game is launched.
I believe a new .sol file is created if (a) you're launching the game for the first time, (b) you've moved the Machinarium folder, or (c) you take out the existing .sol file and do not substitute another one.