I highly doubt that most of you have put years into developing great RPGs that rely on terrain and interiors..
I slaved for months and months over a hot laptop making the interior for BL_Construct, choosing textures that looked similar to GM_Construct, making it as close as i could, aligning it to the brick grid the best i could, some areas can't be sealed using only bricks, you need one or two plates, that bugs me, but i'm not going back to fix that little issue, then i had to make the lighting good enough for the map since the way lighting works is different from the Source Engine, rotating the sun, fixing the water, adjusting it's properties, adjusting the terrain to be similar but flat enough to build on, choosing textures for the terrain, blending the terrain with the interior
But now all my hard work is going away, yet i'm still happy and can't wait to have this update
It's not years of work put into a build that relies heavily on the environment, but you get my point