I whipped together a basic editor for Multicolour Go, thought I might as well share it so others can use it to play around with.
Should be pretty self-explanatory, you can click on the board to place a stone, or change a stone to another colour, or remove a stone. Number keys 1-9 will switch between colours, 0 will switch to remove stones.
I will be keeping track of the pilot game on this page, which also shows the usernames next to the colours for convenience.
There is now a save / share board function, so that’s how the game will be shared