Well, one of the core lessons from Fehily is that different systems work differently, so you have to learn about the nuances.
In Manifold you can use the query builder to learn some of the basic syntax requirements. For example, the SELECT template from the query builder is...
SELECT <field>/SPLIT <query>, ... FROM <table>
A SELECT cannot live on its own without that FROM and a table. The simple form
SELECT A as B;
Is wrong. Ain't no FROM there, and no table.
SELECT A as B FROM MyTable;
Likewise, the use of AS outside of a clause that produces a table doesn't work. If you create a table, sure, alias fields.
If you want to just evaluate an expression use ?
? 2 + 3 * 4
See the Command Window topic.
Ah, last but not least, despite the intellectual fun of playing tricky games involving the creation of incomprehensible column / alias names, you might have to escape special characters when constructing the string for the column name / alias. It is far wiser to avoid playing tricky games, since the objective is to produce queries that will not fool other people or you five minutes after they have been written. :-)