Oh. Fair enough.
Sheets editing allows you to change a lot of unit statistics, like hit point, build time, which colony they're available to, etc. But there are certain things that are buildable (regular units) and unbuildable (disasters, mining beacons, EMP shockwave, etc.). These are not controlled by the sheets. You'd need to write a haxed DLL or hack OP2 itself to change that setting.