It's actually a 100x100 grid, each single block is actually 5x5, so in a modelling program you would need to build it on a 100x100 plane. The only problem is, finding the scale, some modelling programs use both global and local scaling, and the global scale units aren't always the same as the units in GameGuru, so you have to work out how to adjust the scale before you model.
For those who use blender i have attached a blender file that is just a single plane with the scale set for GameGuru's 100x100 scale to use as a template for building snapping models if you want it. You just need to make sure that any scaling you do is done in edit mode only, if you scale in object mode it will change the global scale and not snap.
Also here's a little tip for making snapping models, when making snapping models that will be different sizes, for example if you wanted to make a large and small paving slab, but need them to be able to snap two small to one large, then use either odd or even number for your sizes, but don't mix odd and even.
For example:
The small would be 100x100, the large would be 300x300, and an extra larger would be 500x500
or
The small could be 200x200, the large could be 400x400, and an extra larger could be 600x600
but..
A 100x100, would not snap well with a 200x200, this because of the origin point offset in snapping, a 200x200 square is actually only 50 bigger on each side than the 100x100, so you're only giving it half a grid extra offset from the origin point. Whereas a 300x300 would snap perfect because it is 100 larger on each size, so offset from the origin by exactly one grid
I've also uploaded a set of roofs made using this template to
my free models post, i've emailed Lee these models too, hopefully they will be added to the entitybank/fixtures/roofs folder in a future update.
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