I have managed to update we-no-limits to support tft. If you have never heard of this app it does the following: Removes Unit/Doodad/Item limits that blizzard has placed in that stop you from saving once they are crossed. Enjoy!
The new version supports all different releases of the World Editor including different localized versions and special WEs such as UMSWE and WEU since the release of TFT (1.07) up to the latest patch (1.20). Just make sure to select the correct version. In addition to the Unit/Item/Doodad limits, it also removes an error message when changing the map properties on huge maps (like 480x480).
WE-No-Limits - TFT 1.19
<- works for 1.07 - 1.20