Thanks for the input. Health department says wood is fine, as long as sealed. It is because of my anticipation of them saying they might be too wide of gaps that I have been looking to fill them with something. There are far too many for me to fill with something like the 2 part min wax. I used that in some areas but have stayed away from the many gaps with that stuff. I have spent about a year on this floor, so I hate to give it up now. I am really discouraged that I can't find a solution. Everyone says that wood filler will crack and come out eventually, however good it is, caulk won't work, too flexible, I don't think I can just ignore them for health code reasons, (they should be sealed). So... filler is too stiff, caulk is too flexible, Nothing I can do??? I was reading wear the gym floor sealer is very flexible, much more so than polyurethane. Maybe that would work over Acrylic caulk. According to the "White Lightning" label it will seal gaps up to 1" wide and 1/2" deep, and can be painted. Maybe the gym seal that is flexible will work over that? One person told me to use wood glue and rope, but I really don't want to nauticle look. One more thought is to use caulk and an outside wood sealer.