I have reached the second level which is the actual temple level. However, the game crashed when loading a save before that at the end of the "Somehere in Egypt" level when I was searching for secrets. I had to delete/reinstall the entire game (Windows10) and clear the registry, windows cache, etc. to reload a savegame.
Thus, you should save regularly in case you encounter this crash problem which is not from Windows, but rather the builder's tools because this type of save load problem has occurred in previous trle levels that use the same textures, objects, etc. such as the Persia levels, etc.
Also, beware that starting this game may automatically connect to the internet!!! Something that may be triggering the virus scanner programs saying that trle.net (Malwarebytes) and customlevels are bad.