When you export,in the vdb node control panel, turn off the floor is zero, that one seem to yield a wonky offset.
Start with the basics, toroid you have, and make sure the toroid object shape is in the center of the simulation domain, you do that in the simulation node, and set all the zero position on x, y, z axis to center, by default it is a bit different.
Also, make sure your object from blender is in a zero position (until you have understood how it all works anyway and get this right
Scaling in embergen, keep as it is at x10 and 100% scaling.
do the simulation and export, export with meter settings, and use meter settings in blender as well.
Once back in blender, rescale the vdb volume to 0.1
Do not move the object in blender, nor in embergen for a starter, just to check the scale and postion will be right for the basics.
Once that works, you would of course like to have the toroid almost at the bottom of the simulation domain in embergen, so you can have a longer fire and smoke plume, so move the shape object node like minus 10 meter, not the emitter.
Back in blender what you need to do, since it expects a location from center since we didn´t change the object movement in blender, but what you got is the simulation object shape´s vdb smoke data starting from the bottom, so here we have a mismatch naturally, and what you have to do in this case is to move the vdb file up by minus 10meter, or simply move the mesh toroid downs instead by minus 10 meter, there´s no way for the system to sync individual location moves.
Try this for a starter and it should work.
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