Yes, I fill them with white carpenters glue and then while it is wet sand it with 80 grid sandpaper until the gap has the same color as the surrounding. When this is hardened I sand the whole deck with 120 grid. After that I epoxy and glass. The gaps are slightly different from the wood. The paper will clog but that is no problem. At this time I have no pictures. Am skiing in Germany now. In a fortnight I will place them.
Learned this method from a professional boatbuilder who is using thismethod all the time in the woodwoork which only will be varnished.
I tried first to fill the gaps with small slices of wood but was not successfull with that.

Daan