Hi.
I´m just finishing the work for the in game editor i´m using in Formula Cars game, and just made this screenshot, I changed the style a lot and placed the editor panel in the left side of the screen.
The object spawner opens a secondary little window with options to set, not yet finished, but close to it..

I already made an improvment with corners "drag´n drop" style control to set the region limits of the objects to be spawned. Interesting that after develop with some functionalities in mind, I ended up with some I didnt planned but worked also nice, as an example, the hability of move the corners of the selected regions also in the control panel :

The code inside the tool is interesting also to study and see how some functionalities were achieved, so I think this tool altought simple can be very usefull not only to populate or even build complete model only levels, but also to new people to learn.
This tool will be basically free for use, and I´m already setting a C-Lite converted one to contribute.