Save a copy of your project. Just in case, because this is gonna be dangerous.
Add a new Event Sheet. Call it 'Globals'.
Open both your event sheets (the one you have been coding in & the new one, so you have a tab for each one of them.
Click the tab of your event sheet. Select the global variables. Press CTRL + X.
The system will complain. Click Yes. All your events will look messed up. Do not panic.
Click the tab for 'Globals', to bring that event sheet into focus.
Press CTRL+v. The global variables are now moved to the new event sheet 'Globals'.
Return to your event sheet and it will look complete again.
Do NOT include that new event sheet in any other event sheet. Do not go make events in there.
Just use it for all your global variables.
Why ? When not included, those global variables will not re-initialise when you rerun layouts.