Hello, the design of the blocks is made to use pick list with available GPIO.
If you need to address gpio by number, then you can write a wrapper which provides this possibility.
Here an idea how this could work:
You set a variable with the gpio-number to set (here 'gpio') and then send a message to the script resolving the number into the gpio blocks.
Still room for improvements here: The name of the message could be better. And when having many GPIO, the runtime is long for those later in the nested if structure. But there are possibilities to make it better...
With scratch2, you can use 'make a block' to solve this a little bit smarter.