The Bioware blog recently posted about this information, which I'll summarize here.
Mechanics
Earning reputation in Mass Effect 3 is a bit different from the first two games. Rather than earning only Paragon and Renegade points, you can also earn Neutral reputation, so there are 3 types of rep in ME3.
This means you can now mix being Paragon/Renegade without worrying about getting locked out of the more difficult Charm/Intimidate options. When you earn Paragon/Renegade rep, it'll show up as Blue/Red, whereas if you earn Neutral rep, it'll increase your reputation bar's size as a whole while retaining the same blue/red ratio.
Click through for the larger version.
Your total reputation (blue/red/neutral) will determine whether or not you'll be able to pass a Charm/Intimidate block. The lines on the bar are "checkpoints" which serve as gates for more difficult dialogue options. I marked them with the thin lines of red, in case it was difficult to see (this is not my Shep, this is the photo from the blog post).
As per usual, you get rep from completing missions and making dialogue choices. For missions with no Paragon/Renegade choice but still have a large impact, you will get Neutral rep.
Story Impact
In contrast to older Bioware games, you can never actually be the villain in ME3, though this should be rather clear from how they handled the first 2 games. No matter what, you will be fighting to save the galaxy. The manner in which you do it will be what differentiates a Paragon from a Renegade. Also, bullying people into giving you more money or discounts won't be the crux of what makes a Renegade decision in this game. Who needs credits if there's nowhere to spend them because civilized life has been destroyed?
Reputation gain will be based on when you have to make a decision in the game. Here are a few examples of what kind of rep you would get, taken from the blog:
- Confronted on the Citadel by a desperate refugee with a gun, you give her some credits and help her find a place to sleep. (Paragon)
- As a human colony falls to Reaper forces, you order down an orbital strike, brutally killing thousands of colonists to prevent the Reapers from turning them into husks. (Renegade)
- You land at a turian fuel depot taken by Reaper forces and clear it out, enabling allied forces to keep fighting. (General Reputation)
TL;DR
BioWare has finally made a single-player game that lets you make morally grey choices without nerfing yourself, gameplay-wise. Rejoice!
PS3 games are region free but the game saves are apparently not. I haven't used any cross-region games on my PS3, so I haven't experienced the particulars.
Someone does suggest a (fairly complex) method of getting around PS3 save region lock though:
(you need a pen drive, PSP or any other USB mass storage device)
- On your old game/PS3, copy the save to the device. (select it, press TRIANGLE and choose Copy. Choose the device)
- Go to a computer and plug the device in.
- Go to My Computer>your device>
- Open the PS3 folder and then open SAVEDATA.
- Copy the folder to Desktop then delete it from device.
- On your new game/PS3, start a new game and save.
- Copy the NEW save to the device. (select it, press TRIANGLE and choose Copy. Choose the device)
- Go to a computer and plug the device.
- Open PS3 folder again and then open SAVEDATA.
- Copy that folder to a new folder in desktop.
- Now, rename the NEW folder so that it has the same name as the old folder.
- Open the NEW folder. Here you should see these files:
PARAM.PFD
PARAM.SFO
PIC1.PNG
ICON0.PNG
SAVE.DAT
(if there are more files that's fine. Sometimes PIC1.PNG isn't there, that's fine too.)
- Open the OLD folder. You should see the same items.
- THIS IS IMPORTANT: MAKE SURE YOU DO NOT MESS UP. Copy PARAM.PFD and PARAM.SFO from the OLD folder to the NEW folder. If you do it the other way round you'll mess up.
- Delete the saved file from the device. And also delete the OLD folder. Drag the remaining folder into PS3/SAVEDATA/.
- Goto your PS3, select Saved Data Utility, choose your device and find the data. Copy this (TRIANGLE) then you're done. Delete save from device.
Play the game and enjoy. This worked for me -- it should work for you too.
This should work for any PS3 game, ME3 included if ME3 is indeed region locked; and since it's EA, I would go ahead and assume they did as much locking and DRM as feasible.
Best Answer
There is no way for you to simply "change his fate" with the save editor I believe. It does not matter anyway, the only thing he would do if he was alive was:
No matter if you romanced him or not, the only way to change his fate is through the ThaneMOD.