Can't figure out what's causing Marker Errors

[FunkyGandalfCat]

So, in the last two days I have been randomly getting marker errors with my Nifs, I have did things in a gazillion different ways trying to figure this out, even remodeling stuff from scratch, checking flags, check this and that, the list goes on.

I duplicate an static mesh as I did a billion times, browse for the Nif file I just created in the correct folder as I always did, great, it renders in the preview window. I close and save. I then reopen to see if its still there, and it is.
BUT
When I try putting it in a cell in the render window, PUFF! Marker error, and when I open the Static mesh again to check, the marker error is there, from absolutely nowhere.

Here is the NIF I tried last: Bridge NIF

Thank you

[Hanaisse]

The nif is fine, looks good in Nifskope (it's also pretty cool).

I added to CK as a test, it's fine. I added  it to a test cell, it's still fine. In game it's fine.

I'd suggest changing the root node name from Scene Root to something else, sometimes that messes with static objects. Otherwise, try using F5 to refresh your render window.