Are you sure you set the system locale to Japanese or did you just change your PC region? just helping but in order for you to change your system locale follow these steps.
1. Click your start menu
2. Click on "Control Panel"
3. Click on "Clock, Language, and Region"
4. Click "Region and Language"
5. Click on the "Administrative" tab
6. Click on "Change system locale..."
7. Click on "Japanese (Japan)" from the list
After you do that you will be prompted to restart you PC to complete the change. Now that we got that out of the way, click on the program you are trying to run as administrator. and when you get the dialogue box asking you if you wan to run it you should also get a small icon on the bottom right of the screen that says "English", click on that and change it to Japan and then run the program. If this doesn't work compatibility wont be that much help because newer versions of Windows still has code from previous versions of Windows. I'm not saying to not use compatibility mode, I'm just saying that it wont help much.
If all else fails, your PC might be the problem because it's trying to run a program a certain way that the program isn't meant to run and that can cause complications. If this is indeed the reason, I would get a virtual machine granted these are only software and not hardware but it may increase the odds of the program to work. I hope this helps.
