At first, I used this topic to post some findings about acquiring the Masamune temporarily through use of the Jenova Save Game Editor, due to issues i couldn't really resolve, and the harsh reality that it was probably more then likely a fluke, i did more investigation into how to actually get my hands on this blade.
You can do this too, all you need is..WallMarket Tool: http://forums.qhimm.com/index.php?topic=7928.0 a excellent tool by NFITC1 without this, none of this would be possible, so I thank him greatly for this wonderful application.
Final Fantasy Character Editor Ver 1.30: By CH khor, I'll post a link if requested, but you should be able to find it with google/yahoo.
First, open CH khor's Character Editor, go to the Items/Gil Tab, and go to the drop down menu, find masamune, and add it into your inventory, easy right?
WARNING! (Make sure to make a backup of your Kernel in case of unintended results, I'm not responsible if you mess up your game and have to reinstall because you didn't heed this warning)
Secondly, open wallmarket, scroll over to the Weapon tab, locate the slider to the left, that lists all the weapons, Masamune should be the very last entry. click on it. it should open a menu of the stats of the weapon, from there, locate the section that says equipable by, of course, no brainier, check mark cloud (Cloud is the name even if your cloud is a sephiroth from a sephiroth patch or named different in game) or you can also check mark someone else if you want them to equip it instead. Select create kernel from the drop down menus at the top and close..
Lastly: Start up the game, and equip the masamune to Cloud/Whomever you chose.
Side Note: You can also edit the stats of the weapon, I usally do this to match the current level of weapon i should have at the time (giving it buster sword stats at the start of a new game, then pumping it up when i get my hands on each progressively more powerful weapon) You don't have to, it just makes the game a tad more authentic.
I know this isn't much to the great technical people of this community, (you guys are awesome) but hopefully this can help people like me, who aren't as tech savy and need a direct run down on how to get it to work
Special Thanks to:
Ficedula: Thanks for your awesome save game editor, that set me on my mission to find a solution to this problem.
NFITC1: For your awesome Wallmarket tool, that makes equipping the sword possible! you rock!
CH khor: For his save game editor that solved my problem of getting the masamune, awesome, just awesome.
I may be new, and if i put this in the wrong spot, i give my sincerest apologies. I hope I was able to contribute something back to this awesome forum.
If you have any questions just leave a post.