Doors and Windows - PLZ HELP...Time sensitive Veneer door stain

Heavy Veneer Doors (Commercial) Im having a prob with dust getting in the min-wax poly-shade (Dark) I'm using. I've tried using lemon oil and 600 grit to get it clean and smooth which worked well but it's leaving a white haze on the finish. Im also experiencing brush marks but should be able to fix that. Also should I be using a sanding sealer and/or wood conditioner? Please help its time sensitive. Im going gray by the hour.

First, you can't work in a lint / dust filled environment and expect to have a perfect finish. And you probably don't want to wipe on any sort of oily product other than paint thinner... and you would only do that after the finish had a good 24 hours to dry, which is the time I would suggest you allow between coats of finish. Don't use fans to circulate air either, that will only speed the amount of lint and dust flying toward the product.

Personally I avoid polyshades like the plague and only use it if I can spray it on.

Sanding sealer can be used as an initial coat, which seals the wood and sands easily, providing a nice smooth surface. But between coats of polyshades, you should still be lightly sanding with the grain, using 220 grit. 600 is too fine. After you sand, wipe with a rag lightly moistened with thinner.

Wood conditioner is used with soft woods like pine and helps eliminate blotching- sharp areas of contrast that show up when you stain. If you are using polyshades you are probably not staining, and you would not use conditioner.