Casual plumbing advice needed

[Racer X]

ya gots to grease up the rubber when you screw it in.....

[OWC Jamie]

The tail pipe should most certainly come straight down.
It might not leak today. It will eventually.
Depending on what kind of tail-pipe you have, there is a waher there of some sort to make up for slight misalignment. Not more than, say, 5 degrees.

The horizonal pipe is either too short or shoved in too far ?

You want rubber gasket up against the sink surface otherwise you defeat the whole purpose of the gasket.
The other 'washer(s)' could be for between the gasket and spanner nut.
You don't want the spanner nut to contact the gasket, because when tightening the spanner nut, the gasket could twist/distort. Call it a 'slip-washer' if you want.
HTH.
Stay dry.

[ho'ard]

Yes, bought a new set with "slip washer" today. Had it right before.
Also dome "plumber's grease" (doesn't say anything about silicon though).
It's a double basin and one of the pipes are not the right length-- can't get it into the big ugly pipe coming out of the wall any farther.
Will try the double gasket trick.

[Racer X]

I think plumber's grease is by deffinition silicone. It is food-safe and essentially ingestible in the small quantities you could pick up from residue on a valve.

[OWC Jamie]

They make extensions.
If it's that close to falling apart, it will leak, eventually.
Mold under a sink from even a small leak can get rather stanky.