I don't have the 1050, so I will only address what I can.

Most of the sound for movies and all for stereo will come from your mains. Thus, the 4 ohmers in back should be no problem for the 1050. Leave your Outlaw set for 8 ohms to match your mains.

The S-video problem with the 1050 has to due with passing/switching a video signal that is lower than the spec of 1V. There is no fix for this. The Outlaw is just less tolerant of out of spec video signals than most other receivers. The problems are on a case-by-case basis. You would have 30 days to try it out and see if you have a problem. Of course if you only have 1 S-video source, or enough S-video inputs on your TV, you can circumvent the problem and not use the Outlaw for switching. Less convenient, sure, but a solution IF you have a problem AND believe that the 1050 offers you a better value than anything else on the market.

When you say stereo sub, what do you mean? A sub with 2 RCA inputs instead of only one? Read your owners manual for the sub. You should just be able to plug the sub output from the receiver into one of the two inputs on the sub. If not, most receivers will give you fits. It shouldn't matter when the summing of the two channels occurs, in the receiver or in the sub.

Your fourth question I'll have to leave for the others.