Actually, what you are running into here is the export/import errors generated by NWMax etc.
What I typically get is a series of errors like this one (found in that tni01_q05_01):
Bad Edge: 3 Vert pair: [499.996,199.001,-0.0500031],[499.996,250.001,-0.0500031]
If you look at that, and the dozen others that show up on initial export on that tile, you will notice that the entire wok was offset by .003,700.999 from the normal 500,200,0 that it should be.
the last error line:
Bad pivot location. Pivot must be 0,0,z. Not -0.00390625,0.000976562,z shows you exactly why that first (and rest) of the errors occurred.
Clean Models by OldMansBeard will fix those for you easily, OR, you can manually adjust the wok back into position. The issue though is the rounding errors on export/import, Primarily the actual import. It also affects EVERY SINGLE object in a given mdl file. So manually fixing things would take a human forever. Clean Models by OMB is a life saver for this stuff.
Typically, I run CM3 on everything prior to import, and then again, on the resulting final exported tile. The error counts CM3 shows are very large, but most are the rounding issues.
Technically, that small of a rounding error, IE on the first time you import/export, won't hurt much, meaning the game can handle it. Which is why some of the "older" cc folks just turn off sanity checking. However, if you do multiple import/exports on that same mdl, the rounding error grows large enough to truly cause issues. And, if you have sanity checking turned off, you won't find any truly broken bits in the wok.
Anyway, run CM3 on any tile before you import, do whatever you need to edit that tile, then run CM3 on what you think is your final export. Believe me, it will save you hundreds of hours of work that you would other wise have to fix.