Please follow
GPAG - GUI Proper Application Guide for prefix and variable naming to ensure a much cleaner and readable triggers.
I'm not sure what's the purpose of indexing the dying units in your system as I see no reason for it. If you are afraid the system overwrites the value of dying unit, you don't have to worry, because it does not. This is proven by the fact that you can use dying unit with waits. But if you want a safer and slightly more efficient option, simply use triggering unit instead. Still no reason to index them, though.
Also, "DROPing_UnitIndex" will always start from 2 when it has reached a value greater than 70. This is due to how you place "DROPing_UnitINDEX = (DROPing_UnitINDEX + 1)", simply place it in else block instead. But you don't need to use indexing in the first place anyway because of the point I explained previously.
You don't need to null global variable. It is only necessary for locals.
Your system looks more like a template to me. I will not deny its usefulness, however, it is a bit too simple from coding perspective and not user-friendly enough to use from end-user standpoint because they still need to copy/paste the code and change some values for every new table they create. This can also get expensive if they create a lot of tables, because longer code in GUI can cause lag in the editor, I imagine it will be a nightmare to change the necessary values at that point.
A good system is a system that allows the user to not worry about how things work in the background (they don't even need to know how it works) but still allows them to change some values from the foreground aka the config trigger. Most of the things here are done manually by the user except the math, you can instead use a Hashtable to automate the process.
In summary, remove the indexing because it has no use. Use triggering unit instead of dying unit for a safer and slightly more efficient option. No need to null global variable. Follow the GPAG to ensure a much cleaner and readable triggers. Create a more in-depth documentation on how to use your system (Not everyone is a GUI user). Consider using Hashtable to automate the process so user doesn't have to copy/paste code and change the value more than they have to, this however is optional.
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