A quick test result in this: Great plane of home - realy.
1. The v-0.4 reduce the delay from 30" to 19" I try reduce them more (look next version)
2. In tree view the furniture completely disappear with plugin activated. Fixed
3.1 I suggest again to split in to different plugins and focus at ...

Quick Update v.0.4 release (17 Apr 2018) SH3D Plugin Form.
Quick Fix: Removed dependence on custom SH3D build.

v.0.3 release (17 Apr 2018) SH3D Plugin Form.
Issues:
1. Add room floor perimeter and sides.
Fixes:
1. Grouped tree view dragging now worked!
Known bugs:
3. Changing language disturb filtering catalog combobox (Restart solve it).
4. Parameters from setting dialog not saved between app starts.
5 ...

To dorin
About add check-box to main setting window: I think this possible, i try do it in next version.

Thank you dorin for your critics | suggestions.
In tree view are show the name of last piece at the end of the icons row which sometime could be confusing (not for me). I try do something with it, may be split long row of icons by it's count, by 10-12 items may be?
Anyway I've already observe few ...

no offense please, but:
In piece preview are show only the first one: From description of v0.2
Known bugs: 5. Grouped tree view show incorrect toolTip.
Also please look at others known bug, for not spending time of it's searching and reporting:
Known bugs:
3. Changing language disturb filtering ...

In first, tell me please:
in the second window the furniture are multiplied it's fixed on your collection, or i am again can not catch trouble?
In second about critics:
1. If you confuse grayed item in "tool" menu - it's now replaced with "Settings" option (was legacy item) in next version.

find ...

... (no offense please)

why i can do it? [:)]

Like You've seen in the picture in the second window the furniture are multiplied and this is useless.

Fixed in version-0.1

I look in Your sources and I catch my ears; is to complicated for me.

Sorry for this [:(]

Thank you very mush dorin for fast test.
In first trouble, that i see, unexpected trouble is furniture is multiplied, Can you tell or show me your collection with that this redistribute. In my case of furniture collection, i can not catch this trouble.
In second - code for perimeter not activated ...

Here link to SourceForge: SourceForgeLink
[s]2. After switching List->Tree->List selected furniture may be freezed. Only application restart solve it.[/s]
Fixed.