I also play on linux. When the .sh and ./lib/linux-x86_64/* are missing I copy them over from a previous version of the game or sometimes try to copy them from other games entirely. But when it is from a previous version of the game I feel like things have better chances of going smootly.
I'd like a native support for linux, but I don't complain because the work around is simple.
That remind me of a previous post about the .sh not being executable right after extraction and being complicated to make it so under windows.