Level Creation and collisions

I primarily use Blender for my content creation.

I want to render the whole level to a large png, and import as background.

Then, setup the collision polygons in the layout.

I don't think this is possible at the moment. I think collisions are made per object, and quite primitive.

Is the above method a good idea, appreciate any comments.

IF there PNGs then yeah Construct will detect the collision polygons but maybe not as good as your hoping,

Its probably best to make your background a JPEG, and all the main objects individual pngs

using a big png is not a good idea, it's better to try to find repetitive pattern in your design and work with tiled background and png overlay.

You can do some nice thing without killing your VRam.

Anyway, for your question you can use invisible (option in the properties panel) sprite as collision boxes.