yea. id suggest getting a 250w hps and growing from seed. veg like 4-8 plants for 3 weeks then put them in 12/12 light. very easy to do if done simply and properly. grab yourself some nutes if u like. im assuming since it's an attic there's a vent or duct to the outside...so you need to...
wow ok man if u have that many questions you need to check out the growfaq.
ill answer one of ur questions that i dont think is there...foxfarm nutes are what i use/recommend. get the tri-pack with grow big, big bloom, and tiger bloom
well i fly within canada all the time with weed. usually either just roll it in a couple bags and put that in a pair of rolled up socks then put that in a pant leg of a pair of folded up jeans. done it prolly 8 times. but again, that's within canada.
In my opinion they're ready to transplant. I usually keep my clones in peat pots for 1 week - 2 weeks. then just straight into a 3-5 gallon pot. but any longer than 2-3 weeks and the roots will become stunted