If you don't want to bother with a file edit you can always just use the command:
/myst-toggleworldinstability [dimId] [true|false]
Example where the age number is 25: /myst_toggleworldinstability 25 false
The aforementioned command will remove any effects that are applied to you or mobs as well as lightning, meteors ect. I am not sure if this will remove decay blocks, I doubt it.
If you are like me and would like to keep legitimate instability while removing any possible illegitimate instability in an old age you can download a program called NBTExplorer found here: http://www.minecraftforum.net/topic/840677-nbtexplorer-nbt-editor-for-windows-and-mac/
1. Visit the ages you want to update to be sure they get converted to the new format. Close minecraft and BACKUP YOUR WORLD and don't forget to BACKUP YOUR WORLD.
2. Open NBTExplorer, under file there will be a folder icon with a sheet paper in it. Click it.
3. Navigate to your "minecraft/world/data" folder.
4. Find the Age number that you need to edit and open it.
5. Click the + beside "data"
6. Click the + beside "pages: X entries"; You will see a bunch of lines that read "1 entry" (If it doesn't exist you haven't visited the age so it hasn't been updated.)
7. Click "pages: X entries" and it will be highlighted
8. Click the Folder (Add Compound Tag) icon next to the binoculars
9. At the bottom of that section there is a line that says "0 entries". Highlight it by clicking it. (You just added this.)
10. Click the "Aa" (Add String Tag) icon near "Add Compound Tag" icon
11. Type this exactly with no extra spaces or capitalization and click OK (Without quotes): "symbol"
12. Double Click "symbol:" (You just created this in step 11.)
13. Type this exactly with no extra spaces, exact capitalization, and without hitting Enter, then click OK (Without quotes): "ModClear"
14. Click the + beside "Symbols: X entries"
15. Highlight "Symbols: X entries" by clicking on it
16. Click the "Aa" (Add String Tag) icon.
17. At the bottom of that section you will have created a blank space next to an Aa icon, double click that space.
18. Type this exactly with no extra spaces, exact capitalization, and without hitting Enter, then click OK (Without quotes): "ModClear"
19. Click the "Purple Floppy Disk" icon under "Edit" to save your changes. Close NBTExplorer if you are finished editing or go to step 2 and repeat.
If you follow the above steps exactly the Age will automatically reevaluate the instability effects and adjust accordingly once you visit it again. Your old stable ages will have the improper effect removed, and your old unstable ages will still be unstable. You can apply this to any world you have created after you updated to v0.10.0 as well. Essentially you are just writing an extra page at the end of the descriptive book, the "Clear Modifiers" page. You can cheat this individual page in through cheat mode (not cheat mode plus) and add it to the end of all your new ages to get rid of whatever is causing any unwarranted instability.
I've tried to right these steps as simply and precisely as possible. I hope it helps someone.
/myst-toggleworldinstability [dimId] [true|false]
Example where the age number is 25: /myst_toggleworldinstability 25 false
The aforementioned command will remove any effects that are applied to you or mobs as well as lightning, meteors ect. I am not sure if this will remove decay blocks, I doubt it.
If you are like me and would like to keep legitimate instability while removing any possible illegitimate instability in an old age you can download a program called NBTExplorer found here: http://www.minecraftforum.net/topic/840677-nbtexplorer-nbt-editor-for-windows-and-mac/
1. Visit the ages you want to update to be sure they get converted to the new format. Close minecraft and BACKUP YOUR WORLD and don't forget to BACKUP YOUR WORLD.
2. Open NBTExplorer, under file there will be a folder icon with a sheet paper in it. Click it.
3. Navigate to your "minecraft/world/data" folder.
4. Find the Age number that you need to edit and open it.
5. Click the + beside "data"
6. Click the + beside "pages: X entries"; You will see a bunch of lines that read "1 entry" (If it doesn't exist you haven't visited the age so it hasn't been updated.)
7. Click "pages: X entries" and it will be highlighted
8. Click the Folder (Add Compound Tag) icon next to the binoculars
9. At the bottom of that section there is a line that says "0 entries". Highlight it by clicking it. (You just added this.)
10. Click the "Aa" (Add String Tag) icon near "Add Compound Tag" icon
11. Type this exactly with no extra spaces or capitalization and click OK (Without quotes): "symbol"
12. Double Click "symbol:" (You just created this in step 11.)
13. Type this exactly with no extra spaces, exact capitalization, and without hitting Enter, then click OK (Without quotes): "ModClear"
14. Click the + beside "Symbols: X entries"
15. Highlight "Symbols: X entries" by clicking on it
16. Click the "Aa" (Add String Tag) icon.
17. At the bottom of that section you will have created a blank space next to an Aa icon, double click that space.
18. Type this exactly with no extra spaces, exact capitalization, and without hitting Enter, then click OK (Without quotes): "ModClear"
19. Click the "Purple Floppy Disk" icon under "Edit" to save your changes. Close NBTExplorer if you are finished editing or go to step 2 and repeat.
If you follow the above steps exactly the Age will automatically reevaluate the instability effects and adjust accordingly once you visit it again. Your old stable ages will have the improper effect removed, and your old unstable ages will still be unstable. You can apply this to any world you have created after you updated to v0.10.0 as well. Essentially you are just writing an extra page at the end of the descriptive book, the "Clear Modifiers" page. You can cheat this individual page in through cheat mode (not cheat mode plus) and add it to the end of all your new ages to get rid of whatever is causing any unwarranted instability.
I've tried to right these steps as simply and precisely as possible. I hope it helps someone.
