OK, a bit of fiddling later. I've ditched Wayland as my default login with 17.10, and sticking to X-Org, which also allows me to use the nVidia proprietary driver. Another reason not to use Wayland besides AppGameKit incompatibility.
As for my other niggle, was the lack of getting AppGameKit on the dock or dash or whatever it is called. Figured that out as well after a lot of fiddling, and here is the recipe:
1: Open your favourite terminal-emulator, may I suggest terminator, and navigate to $HOME/.local/share/applications/
2: Now create an empty file named geany64.desktop, using 'touch geany64.desktop' in the terminal
3: Edit file using nano (or better yet micro) so it contains this:
[Desktop Entry]
Type=Application
Name=AGK
GenericName=AGK IDE
Comment=App Game Kit
Exec=/home/{your user name here}/AGKLinux/Tier1/Editor/bin/geany64
Icon=/home/{your user name here}/AGKLinux/Tier1/Editor/share/icons/hicolor/48x48/apps/agk.png
Terminal=false
Categories=Development;IDE;
4: There must be an empty line at the end, and obviously, change the {your user name here} to your user name. Also assumes you've copied the AGKLinux folder under $HOME
5: Save file, and then make it an executable - easiest done just navigating to the location in the file-browser (ctrl+h to show hidden files), right click, select properties and make executable. Alternatively in terminal use 'chmod 755 geany64.desktop'
6: launch AppGameKit via the newly created .desktop file. Either using file-browser, or './geany64.desktop' in terminal
7: When AppGameKit is up and running, in the dock right-click the icon, select add to favourites. Done!