Hello all. I've been trying to install sh files in ubuntu 16.04 and I'm running into some difficulties. The only way that I can get the installer to complete is to enter something like this sudo ./thimbleweedpark.sh in the terminal. However, when the installation completes, there is an issue where the executable of the game is missing its icon and when I try to launch it, it says Failed to parse the desktop file. error opening file permission denied.

This is not right at all; you should not be running things as root unless absolutely necessary. Were you trying to install the game to a location outside of your home directory (or otherwise not belonging to the normal user account)?

Just double-clicking on the .sh file in the file manager or running "./<installer.sh>" from the terminal should be enough, but it will need permission to run first. You should be able to right-click it in the file manager & select "properties" or so, then set the permissions from there, otherwise you can open a terminal in the directory the installer is located in and do: "chmod +x <installer.sh>".

To clean up the failed install I'd suggest going to the game's directory and running the uninstall script as root and then try installing it again without using sudo and to a location owned by the normal user account.

Ok, I've figured it out. I had to create another directory where the SH file has permissions to write to. After doing that and setting that directory as the end point for my other GOG installs, the games have installed fine and are running correctly.

how did you do this step by step?

open a terminal, go to the directory you have the installer in (just to be sure, type in "ls" and there it should be) and then type "chmod +x ./<your_installer_filename>.sh", then just run the script by typing "./<filename>.sh".
the ./ at the beginning is important to tell the computer you're running a program, and not a command, otherwise you'll have an error

I think that waiting 3 years for this solution was worth it.

>waits his entire lifetime just to be prompted to restart the computer

You can also just bash ./installerfile.sh and it will take over. that pushes bash to run it without going around to change it's attributes. Bound to come up from time to time.