1) Yes. Although not 1.2M in extra cap room, just 0.7M, because for every empty roster slot, there is a minimum salary cap hold. The first round pick represents a "full" roster spot because it has it's own cap hold.
2) We start with about 15M if neither signs. So if Lou stays for 8M as you assume here, and Amir for a pay cut (which I think is VERY optimistic) of about 5M, then you are left with only 2M. At which point you are better off acting as though you are over the cap and using the full MLE rather than using cap room. Reality is, if both stay, even on pay cuts, there's no way we end up with significant cap room. We'd need to let at least one walk, and the other to take a sweetheart deal to even have 10M to offer a free agent, and in the summer leading up to the cap boom, I don't think 10M gets you a Millsap, for example.