Author abbreviation
For reports, the author(s) is/are often organizations or corporations better know for their acronym than their actual full name. APA style guide recommends that the first citation use the full name with the abbreviation in square brackets. Following that, citations can just use the abbreviation. As it stands, I don't see any way of implementing this in ZoTero. To start, it would be helpful if there was an abbreviations field that could go with each author.
In an nutshell, that's possible with MLZ and the abbreviation filter (both written by fbennett). To start, you can try the abbreviation filter with the "classic" Zotero client.
Short-form institutional names are configured on a cs:institution element (a sibling to cs:name) that is not permitted in standard CSL. The element is documented here. Zotero and MLZ use the same citeproc-js citation formatter, and cs:institution is recognised in both. But there is a second problem, with processor input.
The cs:institution node takes effect only for names that carry an "isInstitution" flag. MLZ applies this flag to all single-field names, but mainstream Zotero does not set the flag. A style containing cs:institution nodes will run in mainstream Zotero without error, but those nodes will be ignored.