You have to cast the webstorage's value.
By default, it is a string, and on start of layout you assign a string to a number.
Result, gametest will probably be 0 the whole time.
On start of layout add a int().
Also on event 7, you litteraly save the value "gametest" (and not the value OF gametest) as it is written in between quotes (string).
Finaly you have to consider that the first time that you run your game, the webstorage is empty.
Assigning its value on stratup will end up by giving you a value of 0 for gametest.
Here's a corrected and working capx
I changed the name of the webstorage key ("save_gametest" to "saved_gametest" as the first one was filled with a "gametest" that made the rest of the code not work).
The only bug was in the code, sorry.