Just read ALL of the listed steps, ESPECIALLY the steps for how to navigate around in your particular TV's service menu from your remote because it's NOT stratight-forward and you can easily select or change things without intending to by assuming you know which buttons should do what for moving around in that menu (but don't let that scare you, just be careful and don't "assume" anything!), then just follow the listed steps to enter the menu and look for the applicable menu section as described for your model of TV, and then once you've found the section pertaining to EDID Write protection (whatever it may be called for your TV) switch its' setting to the opposite of whatever it's set to when you find it (ON to OFF or OFF to ON) and then STAY IN the service menu the whole time and just look through it to what's showing on the TV's screen behind it from the PC to do the powerstrip process.
I switched the setting, exited the service menu, then tried powerstrip and kept getting an error that suggested a cable length problem when there wasn't actually anything wrong with the cable I was using whatsoever.
When I got the error several times in a row I decided to stop trying and went back into the service menu to switch that setting back, thinking I'd just give up for a while and try again later, but instead I found that the setting was already switched back on its' own which apparently happens automatically (at least on my A650 "6-Series" Samsung DLP) whenever the user exits the service menu and that was exactly why it hadn't worked for me, doh! Essentially, exitiing the service menu put the EDID Write Protection back in place so powerstrip couldn't write the info and was giving a generic failure error message that was its' equivalent of "check the cable or use a different one and try again" as a result (a.k.a. "is it plugged in?" for all you tech guys...
Also you won't see any apparent difference stated by powerstrip as you do the Update EDID steps twice but be sure and do them TWICE exactly as stated in the OP's instructions even though nothing shows up different in the two steps other than which of the two files you choose for the two times you do it, the first time you'll point powerstrip to the main block file and then the second time point it to the extended block file, both of which you created from the two Mitsu modified EDID data blocks listed for your TV in the OP. You must do both steps just to be sure you get the FULL EDID updated as is strongly recommended by PlumB even though it may appear to mostly work with just the first half of the EDID updated which isn't the right way to do this and can cause other compatibility and functionality problems that I'm not sure the details of!
It sounds complicated but it's really not hard once you get the PC working with the TV's HDMI port.
I don't know if PC resolution makes a difference but I'd suggest setting the PC to 1920x1080@60hz before you begin just to be safe, or maybe the ____x720 equivalent size/resolution in your windows display settings.