Issues building basement, all known workarounds failed?

[Awbee]

I have been trying to add a basement to this house, but I keep coming across 3 issues. I've tried EVERY possible workaround suggested.. If it can be found on the first 10 pages of a Google search, chances are pretty high that I've probably already tried it. (but it doesn't hurt to suggest something).

Here are the problems..

1) The Basement/pool tool will immediately crash my game whenever I click on it, unless I bulldoze the lot & place my house back onto it before clicking the tool.

2) When the basement tool doesn't crash my game, the basement walls just won't appear. I recorded a quick video showing what I'm talking about. http://www.youtube.com/watch?v=IrDf0yRZSIY

3) Whenever the walls do appear, I get 'no support' & cannot continue building ANYTHING, If I try to use the basement tool while on B1 the game will CTD.
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The house I'm using is a modified version of http://modthesims.info/download.php?t=355470 (The Manor Estate: by pereira) His version supports basements, my version doesn't.. I don't know what I changed that caused my version of his house to become corrupt & not support building a basement..

I was originally planning on taking his 'artificial basement' & turning it into a real basement using the basement tool..

I'm going to be offering up the option to download my version so you guys can take a more in depth look into it & hopefully we can figure out what caused the issue.. (No CC required, i typically don't mod my games.)

DOWNLOAD LINK: http://www.mediafire.com/?o8aoumi9a9e3b58 (The Manor Estate: by Awbee!)

[simsample]

Just to be clear, this only happens on that one lot? Or does it happen in other lots?

[Awbee]

Just to be clear, this only happens on that one lot? Or does it happen in other lots?

I've tried placing my version of the house on various 60x60 lots in Sunset Valley, Riverview & Twinbrooks, I can't seem to get a basement on any of them.. However placing the original house on any of the same 60x60 lots results in being able to build a basement..

[whiterider]

Perhaps this (http://www.modthesims.info/showthread.php?t=383083) is what you mean by "bulldozing the lot and replacing the house"; in any case, that's the only workaround I'm aware of.

[Awbee]

I had already tried that method before, but decided I'd go it a go again anyway..

While in the process of "deleting" the pool/basement using the hammer, I hit a snag & couldn't delete part of the basement because something was in the way, so I hit Ctrl+Shift+C & input "Testingcheatsenabled true" followed by "Buy debug" whenever I hit enter.. This little white block named "Should not appear in game" appeared.. So I moved it upstairs using "moveobjects on" (somewhere easier for me to locate it)

http://i1159.photobucket.com/albums/p629/Ikaura/TS3W2012-04-0507-19-54-07.png
I'm guessing this little white block is my problem & I need to find a way to remove it, so it doesn't cause me any more issues?

[whiterider]

That is interesting - I suspect it's a pool marker, to tell the game where to spawn water. In the knowledge that doing this might break the lot; can you delete it with moveobjects on? How about using the sledgehammer?