All right....
I don't want to give you all my pictures at once then I would lose you all again so I'll provide pics as I have progressed these past few days.
After painting the kids area I needed to get the floor buttoned down before I did anything else.
I had figured I would only need 4 to 6 nails to do the job, but this was not the case. I needed at least 6 in some of the smaller boards.
The process was/is to drill a pilot hole through the OSB then use the hammer drill to drill into the concrete floor.
Here are the tools. The big DeWalt drill I borrowed from the guy who did my drywall. My Hitachi is a hammer drill, but it does not have the umph that the DeWalt does.

Going to work with the big drill.

I was very surprised at how well or at least how much easier the DeWalt drilled through the concrete vs. my Hitachi. No comparison, just another example of why it is important to have the right tool for the job.
Once I drilled the holes I placed a piece of 12 gauge copper wire in the hole.

Then the fluted masonry nail to button it up.

Lots more holes than what I had thought and took more time too, but was easier than I had planned due to the bigger drill. I am really glad I did the sub-floor my basement feels just like the main levels underfoot and you don't get that cold feet feeling. Still need to button up the theater and the kitchenette but that is just going to take some time.
I'll post some more progress pics later.
Regards,
RTROSE