let me follow up with 1 and 3 as soon as possible more detailed

3: please check your coupon code (not the name!) of a newly created coupon is starting with "template_". in the winback advanced module you should only see that coupon. (let me double check later)

regarding 2:
the test email is there to send a quick test.

to have a real preview you can run everything in simulation mode.
in simulation mode you can test everything incl generation of coupon. in simulation mode the coupon code are starting with [SIM] and there will appear a button on the top level to delete all generated simulation coupons.
see also section "simulation" under tab configuration for further options.