To take a picture of your screen, there are a couple of different options. Your computer will have a built-in screenshot capturing function, but how it works is different on each operating system (e.g. Windows/Mac/Linux.) You can also use a screenshot capturing program, they usually have more features and built-in functions like cropping and uploading; I’d expect there are some free ones available online.
Instead of a screenshot, you could also upload a save file – that lets the developers see exactly where the stuck hearthling is, and what’s causing it. To find your save-game, look for the Stonehearth folder on your computer, and in there you’ll find a folder named “saved_games”, inside that folder will be your save files but they won’t have names, they’ll have numbers. However, if you look inside each save file’s folder, there will be a text file named “metadata”, and one of the lines in that file will have the name of the save that it corresponds to – that way you can make sure to send the right one
To upload a file (whether it’s a saved game or a screenshot) to these forums, you can simply use the function in the post editor – there’s a button along that top bar which has an arrow pointing upwards. That will let you send the pictures and files without having to worry about uploading them to another site and linking them (which is what you’d normally have to do.) I would guess this is one of your first posts though, so you may not have permission to use the upload function yet – in which case, I’ll call @moderators to help out. Also, if you are new, welcome to the Discourse!
I hope you can get this issue resolved soon. It’s really odd that it only happens on one of your computers, so I’m sure that the dev team will be glad to have the chance to see what’s going on there!