no problem - i know that from myself - SU and REOTIO stopped for some time, because I couldn't make scenarios, because Orbiter was unable to save scenarios... (solved now - there were just to many scenarios in the scenariofolder...)
so I think since it is not your fault: no problem!
Or more elegant:
let the player find a button with wich he can destroy the spawner.
I can build it so that the time the player needs to find these button is excactly enough for one Ghast to spawn.
That's what I'll do than - later. For first you have to set peaceful as soon as you killed one ghast and set back easy again after returning t earth.
There's a sign in the entrance of nether wich says I made it a bitsome easier.
I plan to do it, but I didn't finish this til now, so you turn on peaceful AS SOON AS you hae killed one ghast (ghasts are those flying ... things)
because I want to delete all the GHAST-spawners and than let only one GHast stay in nether.
If this will not be possible I plan to make a trap at the spawner wich makes that the spawner gets destroyed (by a single TNT-block) as soon as the first GHAST leaves
that's because I think this Ghasts are really cool, but when the player has to fight many of more than one or two of them down it would be to hard...