getElementAlpha/setElementAlpha return false for building and projectile elements.

[FileEX]

Describe the bug

For projectile and building elements, getElementAlpha/setElementAlpha return false.

Steps to reproduce

crun b = createBuilding(1337, me.position)
crun b.alpha -- false
crun b.alpha = 0 -- false

Version

N/A

Additional context

No response

Relevant log output

Security Policy

• I have read and understood the Security Policy and this issue is not security related.