explanation of sfx advanced settings

I'm confused with the advanced settings page for sfx:

Okay, slippage makes sense to me.

but then I look at the info text for price tolerance, and it seems to be to be the very same thing?

Then there is also the expiry time for price tolerance. Does that mean that the price tolerance will rather make the order behave as a limit order?

while the slippage make the order behave as a market order?

finally, what is the use case for post signal validation?
it only says that post signal validation is used to assess whether a price is close to hitting a target point.
it doesn't state what happens if it is.

Can you provide concrete examples for each of the advanced settings?