I am happy you enjoy your VT1-535 kit.
We had a mixup of M10 vs 3/8UNC bolts from a supplier a few weeks back and our warehouse crew did not catch it until ~3 kits went out. We thought we had covered all those kits with new bolts already, but apparently one slipped through the cracks. New bolts are available free of charge, or you can get a refund if you get them locally. We are very sorry for this inconvenience. It is not really possible to install the M10 bolts as they will not even start to thread to due being slightly to large.