compactmachines3-1.12.2-3.0.18-b278

I have the following script which I've used for testing.
https://gist.github.com/wormzjl/3be408cca63d621d5c1b15bb70f95d5e
It shows correctly in preview

However when placed in world it's not recognized by the projector.
Does the miniaturization work with block with orientation such as stairs?

This was easy. In your 3x3 recipe for the field, an air block is represented by an underscore "_", whereas your script uses a hyphen "-". This looks the same in the preview because it's trying to render a "null" or void block in the corners, which looks empty, but when it triggers the field it checks for a "null" which doesn't exist as a block state, and thus the recipe fails.

Closing, this is resolved.

i having the same issue but i wanna make a bigger compact machine size instead of a13x13x13

Making a bigger machine size past 13x13x13 will never be possible, as those dimensions would extend past one chunk and would break a lot of the mod.