Chrome, can I ask where Miss Dansk, Chieftilla and Vanquished ran? I can't seem to find them.

Anyway, I don't mind backing 100 raters with form something like this:
Saturdays only
Last start exactly 7 days ago
At least 1200m
At least 2 starts from a spell
At least 3 career starts
Placed last start or have a c or a b in their form.

On Saturday, qualifiers were:
Doom R4-3 Omnitrader -
Doom R8-8 Miss Gloryhunter WON
Belm R3-8 Arctic Park WON
Belm R4-4 Hero Mak WON

And another one in relation to your first-up idea:
Saturdays only
First-up
At least 3 career starts
Won first-up before
Has a c or a d in it's form

Saturday's qualifiers:
Caul R7-15 Harley Ma -
Belm R7-8 On Target WON