You don't need "item missing" events, delete them. Also, if you want to set 20 variables, it will be a lot of code! It's easier to add them all to a dictionary and save the dictionary. See this demo project:
https://www.dropbox.com/s/1cz1k5x3teikbv5/DictionaryLocalStorage.capx?dl=0
Here is how I usually do this:
On start of the game I call StorageLoad function. At the end of each level I call StorageSave.
good idea.. i talking about whit other guy.. i try.. have added.. and not know how to add global variable or sprite or other in dictionary