It is perfectly ok to spray in cooler climates as long as the paint is of the correct viscosity.
Warming the item to be sprayed will help to hold the paint by accelerating solvent evaporation.
The reasons for orange peel finish is usually uncleanliness, or laying the paint on too thick.
Metholated spirit is not a great choice for clean up, the surface should be washed with water and then wiped with a prepping solvent. A tack rag should then be used to remove traces of remaining dust.
Rubbing down between coats is recommended to make a key for the next coat, unless you use the wet on wet method.
The golden rules when painting are, preparation, preparation, preparation and using just enough coats to arrive at the final colour.
One full coverage coat of clear is ample.
Pouring on extra paint only leads to problems with chipping.
Extra clear coats only give depth to the colour and make for a better gloss shine.