Leaky tub drain

I just installed a new drain cover into a recently reglazed 1927 tub. I put the rubber gasket between the drain pipe and the underside of the tub. I put plumbers putty between the drain flange and the bottom (reglazed side) of the tub. To make a long story short... it leaked. Did I just not put enough puty in? I screwed it tight so the rubber gasket should have sealed it even if the putty didn't but I had a drip coming through the light fixture downstairs after my wife took her shower this morning. It is definitely coming from the drain. Is there a trick to this that I do not know?

Not Enough Putty!!!

OK this is why i ususally pay a professional plumber to do this sort of thing. I removed the screw-in drain flange and discovered that indeed there was a part where the putty had slid over and bunched up, leaving a gap in the seal. I applied LOTS more putty, and reinstalled the flange, and leak tested it with a 1/2 full tub. NO MORE LEAKS!!!
Word to the wise, from the dumb and inexperienced: Always use more putty than you possibly think you will need. let the excess squish out (technical term I think). Thanks for listening. I'll be back when I shart the kitchen this summer, unless something happens between now and then Which, with a 78 year old house is always possible!

How Much Putty? How Much to Tighten?

I have a similar problem now. On a newly installed bathtub, I'm putting in a PVC drain "shoe" that has a rubber gasket and a metal screw-in drain. There are leaks. I've used plumber's putty. I've tightened it with a wrench.

By the way, I'm using the handles of an adjustable wrench fit down into the strainer/drain and I use a big monkey wrench to turn the handles to tighten the drain shoe. It works nicely but I know there are better solutions.

My questions are:

1. I put tons of putty in and almost all of it squeezed out.
2. I tightened this assembly and I'm wondering if I can tighten it so hard the gasket deforms? I'm worried about breaking the tub (Americast), too, though that seems unlikely since I'm exerting a symmetric pressure on the drain area.

Of course, breaking it now while its still not completely installed is better than doing so later when I get the surround installed. The question is important though - how tightly can I tighten down on the basket / drain shoe?

What if the water is leaking past the threads on of the PVC shoe instead of past the gasket?

Can I put plumber's putty on the gasket or is that a bad idea? What about a layer of it on the drain shoe where the gasket meets it?

I've tried teflon tape on the pipe threads, too, to no avail....