The Cloud Defensive Rail System is compatible with Mil-Spec upper receivers and low profile gas blocks. So it will work on a Springfield Saint as long as you have a low profile gas block and not an A2 front sight gas block.
Yes, the Cloud Defensive Rail System will work with a Daniel Defense Upper.
Yes, the Cloud Defensive Rail System will work with a Ballistic Advantage Upper.
This Cloud Defensive Rail System is not compatible with the Aero Enhanced M5 Upper.
No, This will not work.
These Cloud Defensive handguards are not piston system compatible.
Cloud Defensive notes that this handguard is compatible with low-profile gas blocks in the carbine and pistol configuration will work with their handguard. Here are a few that will work for your rifle:
https://www.opticsplanet.com/seekins-precision-low-profile-adjustable-gas-block-750-diameter.html?_iv_code=SKP-RGB-LPAGB-0011510031
https://www.opticsplanet.com/odin-works-low-profile-tunable-gas-block.html
https://www.opticsplanet.com/jp-enterprises-750-adj-gas-block.html
It is not possible to guarantee a color match between companies due to parts being finished in batches in likely different facilities. Batches even within the same company can have slight variances in color.
Yes, that model of gas block will work with this handguard.
Code 2S5-HZ-CDNN-CORV2-FDE and 2S5-HZ-CDNN-CORV2-BLACK come with a BCM barrel nut assembly.