…in Tabletop Simulator. It took a while, but I finally managed to make the leap. And it only took two nights or so to import the graphics, make components, and create snapping points to make a playable version of Staking the Throne.
My regular gaming group gave it a go… and indeed: the game could be played, playing didn’t take that much time, and the game worked (or let’s say it had its moments). The game was definitely not perfect, but it was a good testing session.
Regarding Tabletop Simulator, there are plenty of good reasons for using it: a lot of functionality exists already, prototyping is faster, prototyping is cheaper, and there are more possibilities for playtesting. Unfortunately, there’s a bit of a learning curve… and when you do want to play/test with your friends, you need to get them to buy it too.
For completeness sake, the other framework out there is Tabletopia. On afterthought, getting a framework for online prototyping is a no-brainer for an enthusiastic game designer. Assumably in the end the framework probably does not matter that much, as each of the frameworks has its strengths and weaknesses. So if you are hesitating about online prototyping… stop thinking and start clicking instead.