1-2. You are welcome.
3. It seems to be working for me, so I'm guessing it has been resolved since? I'm seeing the following results for 7-12 when entering 'a' into the search field: https://i.imgur.com/Uknp27S.png
The trigger is affected by the minimum character count as well. I believe you might have changed it to 1 from the default 0. If you change that back, it should start working again: https://i.imgur.com/nFiwj0l.png
Q2: default sorting on auto-populate
I believe you have the auto populate feature set to 'random results'. That feature selects random results by forcing a random primary only ordering. It's because of a database query optimization technique, so the items are not re-ordered.
A possible solution is to use the following configuration for the auto populate feature: https://i.imgur.com/WfJJCmV.png
The search will be performed on a 'empty' search phrase, but treated as a regular search, so the default ordering will be perserved. However this will not yield random results.
I hope this helps!Best,
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