Joy items Vanishing When Built?

[BlueTressym]

I've got a weird glitch going on with Joy Items.  I have taken screenshots of the process bur basically, I can put down a blueprint ok, materials are fetched as usual - and when the builder lays down the last of the needed materials, the building vanishes, leaving an empty space and confused-looking builder. 

Decided to try with a different item.  It seems the materials are delivered fine, but when the builder goes to complete the actual building, THEN it vanishes. 

I have no idea what's going on; the glitch ONLY seems to affect Joy Items.  I can't try with a TV as I don't have them yet. 

http://steamcommunity.com/sharedfiles/filedetails/?id=906934337  Blueprint OK

http://steamcommunity.com/sharedfiles/filedetails/?id=906938997  Materials

http://steamcommunity.com/sharedfiles/filedetails/?id=906945584  WTF?

http://steamcommunity.com/sharedfiles/filedetails/?id=906974661  Different item materials

http://steamcommunity.com/sharedfiles/filedetails/?id=906974998  All materials delivered

http://steamcommunity.com/sharedfiles/filedetails/?id=906975586  Builder comes to build - WTF?

Output log here:  https://drive.google.com/file/d/0BwyFUledpohmV1d3dHdnek5QN2s/view?usp=sharing

This has only started happening in my latest start.  In my last start, I had a glitch, but it was different; I had the game telling me I needed a joy source after I'd already built one.  I mentioned it on the Workshop at the time but since it wasn't actually causing me any trouble, I didn't worry too much about it.  No idea if it's relevant or not, so thought I'd mention it just in case. 

I also have the game telling me on this start that I have 'animal starvation', even though they are not suffering malnutrition and their food level is fine.  This came up as soon as I gained a tame animal (didn't start with a pet).  Just wondering if that might narrow down likely causes...