Hi, right now it is not possible to distribute portable app that needs admin privilege.
The only way is monkeypatching the portable template here: https://github.com/electron-userland/electron-builder/blob/master/packages/electron-builder/templates/nsis/portable.nsi#L5

As far as i see it is not even possible to use a custom script for portable app because if the target is portable the script option will not be considered.
https://github.com/electron-userland/electron-builder/blob/master/packages/electron-builder/src/targets/nsis.ts#L178

Is this something that could be fixed or is there another way i'm not aware of?