Nice! ^_^
Anyway, remember how you set the estate grounds as it's own region,
so rain wouldn't visibly fall through various external bits of the house, like the loo, and the workshop area?
While I was beta testing, I also decided to test various other mods & such as well.
I finally got around to testing the latest version of the Morrowind Code Patch.
When I went to see the house, I brought the weather changing spellbook from my "Forgotten Heresy" mod.
(Due to how you set the weather region, I had to leave the estate grounds to cast the spell, then walk back in, to get the script to work.)
I cast my rain spell, and went to the loo, and the MC workshop. Thanks to the Code Patch's "weather effects have collision" feature,
the rain didn't go through! You can stand in either place, and the roof will keep the rain out, and you can still see the rain through the windows.
(It's relaxing, to sit and watch the storm howl outside, while you are nice and dry inside.)
I was thinking, maybe you could make a small addon plugin that leaves the estate grounds as it's own region,
but sets the region's weather to allow rain and storms.
(Perhaps something like 30% sunny, 20% overcast, 30% rain, 20% thunderstoms, or just "Azura's Coast" standard.)
Also, if you are interested, I could make a weather control script for you, that will allow the player to control the local weather. (On the estate grounds.)
I could design it for use on an activator.
Hmm, perhaps you could use it for a "Weather Control Crystal", that the player could earn as reward for a quest.
This crystal would be placed as an activator, outside on the estate grounds.
Weather control has a variety of practical applications, if you use certain mods.
Like mods that effect sneaking, vampiric weaknesses, and various other things.
(For example, with a mod that affects vampire sun damage based on weather,
you can could summon up a thunderstorm, and walk outside safely during daytime!)
This script would only affect the estate grounds, but due to the way Morrowind's weather system works,
the weather would keep going for a short while if you left the grounds into another region, but slowly change to that region's weather in a minute or so.
(That's how I was able to test it, I walked out of the grounds, to the "Azura's Coast Region", then cast the spell, and then walked back in.)
The "weather collision" feature of the Code Patch works really well. I didn't see any extra slowdown or anything.
So, what do you think? I could even make the script for you if you want, and it would be a nice quest reward.
(A fun feature for the house, too!)
If you don't have a copy of the Code Patch, but want to try it, look here: http://www.fliggerty.com/phpBB3/viewtopic.php?f=53&t=1008