FOUND THE SOLUTION!!!
After hours trying several ways to bypass this stupid block, I found a glitch that allows you to bypass that!
You must do EXACTLY those steps in this order:
1) Open the software installer you want to install. It will open the “It’s time to update your device” window. KEEP THAT OPEN! (Must be open to work!)
2) Open the Task Manager (CTRL+ALT+DEL), go to "DETAILS" tab, look for "smartscreen.exe" and END TASK. (Only works if you end task in "DETAILS" tab! If you end task in "Processes" tab, it opens itself again, and block again)
3) Look at your TASKBAR! You will see the installer asking permission to initiate! Initiate it, install your software and be happy!
My girlfriend's laptop is old and didn't have enough space to update Windows and App store.
Hope this help other people in similar situations! =)