Meshes can be kinda hard to grasp for people new to making games or unfamiliar with 3D... and the ways of rotation you can do with them is kinda limited by default means. They're most easy to use with topdown 3D stuff (or completely sidescrolling stuff) - anything beyond that requires a lot more thought and math to pull off. I was thinking about using meshes for my danmaku thing but ditched the idea for now since I couldn't be arsed to think about the math involved with moving stuff through the screen properly.
EDIT: The mesh editor itself is simple to use and easy to grasp, and so is loading meshes at runtime. Doing UV distortion stuff via the events is where things get a bit more complex, and that's what is required to pull off basically all the 3D stuff people have been asking about.
Yeah, that's true, I wouldn't want to try model anything too complicated with them either (would be like modeling in Sculpt3D all them years ago *shudders uncontrollably*), but various shaped surfaces and using the normal map shaders for the smaller details, they look to be quite capable.
They look to be perfect for the shoot-em-up environments though. I was looking at R-Type Dimensions earlier for the XBox, and the sideways scrolling view of it's 3D mode could easily be duplicated with them, including a small number of actual enemies, while the rest could be pre-rendered to appear three dimensional. Though don't know how one would go about getting the realtime lighting effect.
BTW turns out the mesh was loading correctly, just the amount of displacement wasn't matching once inside construct and became unnoticeable (but I'm not giving up yet! lol).
I think most people who are using 3D in Construct are using some combination of 3D boxes and 3D mesh distortion. There are a few open bugs on the tracker about both though, which might be preventing more people using them. Daiz raised a good point that generally 3D stuff is harder, more mathematical, and more difficult to reason with in your head, which is why 2D is quicker and easier to use.
Yeah, the more advanced 3D stuff is going a bit overboard for a 2D app IMO. Though I love seeing what people manage to create with them. I could certainly see them being of great use in top down games like Diaz mentioned just then too. I suppose it's possible to layer them (since they are still 2D sprites), so suddenly "flat" tree canopies would have all kinds of depth to them, banks of rivers would appear to dip into the water, even some kind of isometric feel to larger buildings. Hell I didn't think of that earlier, wow, awesome! lol.
Seems like they're useful and capable of quite a lot of subtle little tricks and effects before even having to worry about how to rotate them in 3D space (which even having worked in 3D most of my adult life, I wouldn't be able to do via mathematics lol) or other advanced effects. Course I'm still thinking of more basic usage for them, more along the lines of enhancing 2D a little, rather than replacing it like I understand many are hoping for. Since I'm still in the "construct should remain a 2D app" camp and it's unlikely I'll change my mind on that.