In response to your last question, the Reallocation process uses the balance in the account; it doesn't look at individual transactions.

For example, if the Utilties account had a balance of $1,000 composed of 10 AP invoices, it is the $1,000 that is reallocated in a single entry, not the 10 lines.

That's the way it works now. However allocating by individual transaction would be a nice enhancement in the future.