Hello
I just had this same problem. You need to make sure that when you export the model and Instrument data from Spotlight your Units are in Meters and not Millimeters like mine was.
Capture will overlay it's fixtures onto your model so it's best to export the DWG from Spotlight with the fixture layer turned off. Then when you import fixture data into Capture the Capture fixtures will be in the place of the Spotlight fixtures and should be in the correct positions on your model.
Hope this helps.