it says RGiles hasn't been active for almost 20 months, and I kinda assume he's not back any sooner...

It's been a very long time of practice to link back to this thread and give credits back to Rgiles for his transparent tiles in cases of lot uploads...

So, I'd assume one can carry on this common practice for Rgiles' tiles...

Yet, if still worrisome, one can always learn how to make transparent tiles for one's own purpose.
1. RGiles's Tutorial: Transparency in Floor Tiles (Updated 16 Apr)
http://www.modthesims2.com/showthread.php?t=37846
2. Frillen's Tutorial: Transparent Floor tiles
http://www.modthesims2.com/showthread.php?t=71559
3. Modding - Floor Tile: Settings for 2-sided/doubly-sided, animated, caustic pool-tile, and/or pool-surface-tile tiles (20070106 Update)
http://www.modthesims2.com/showthread.php?t=155779

Good Lucks...