From what I can see here, all the necessary files are in place although it's surprising that your file extensions are not showing for some of the files.
What I really think is that you were using Crtl+S to save your terrain but that doesn't work.
If I'm right, you can toggle the base icons to see them (right click the Map window).
Based solely on the time stamps, it looks like you used artik's program, which is very good, but when you transferred from the original greatlakestl, maybe the htz elevation array and possibly the htz ground types didn't come over the way they are needed. Or like I suggested, they weren't saved.
Make a copy of your grtlkstl folder to protect your work, and then...
In the TE, try Importing the height.raw elevation file. You should see your elevations come back.
Then if you don't see the proper ground types, Import the splatetype.bmp file.
If all is well, save your work but not with Ctrl+S. Use the File Menu Save.