Cannot Build and design a house!

Hi,
I cannot seem to build in game. Affects both designing a custom building as well as building a pre-designed house.
Please note the problem is in the design phase of a custom building: for example I cannot lay foundations when I use the design tool.

The code is listed below when I try and build a pre-designed house:

develop-2998 (x64)
stonehearth/lib/build_util.lua:542: assertion failed!
stack traceback:
[C]: ?
[C]: in function 'assert’
stonehearth/lib/build_util.lua:542: in function 'unpack_entity_table’
stonehearth/components/floor/floor_component.lua:104: in function 'load_from_template’
stonehearth/lib/build_util.lua:112: in function 'load_structure_from_template’
stonehearth/lib/build_util.lua:120: in function 'load_all_structures_from_template’
stonehearth/lib/build_util.lua:124: in function 'load_all_structures_from_template’
stonehearth/lib/build_util.lua:434: in function 'restore_template’
stonehearth/services/server/build/build_service.lua:1503: in function 'build_template’
stonehearth/services/server/build/build_service.lua:1494: in function 'cb’
stonehearth/services/server/build/build_service.lua:1469: in function 'do_command’
stonehearth/services/server/build/build_service.lua:1493: in function <stonehearth/services/server/build/build_service.lua:1491

Thanks

Hi,
What predesigned house are you looking at? Is it a custom template you made yourself or something the game provided as a template? If it is a custom template, it’s possible that template has become corrupted somehow … (if so, please upload the template). If it is something that the game provided (like one of the ascendancy houses), please let me know which house.
Thanks
-Yang

Hi Yang,
It affects both custom and game provided templates. When I try and select a template and place it down on the ground it just disappears and the code that I posted pops up. Also I cannot do anything on the design builder itself - it just disappears when I try and place it on the ground too.

Cheers

EDIT: I have figured out the problem.
It seems that if I try to build the custom file first it just causes the whole build tool to fail. However it works fine if I just don’t try and build the custom template.
I hadn’t realised this earlier and so always tried to build the custom first.