After a series of steps, involving re-retrieving, re-refreshing and re-deploying got it work. Not exactly sure what finally made it go through. I kept looking in the IC log for any useful entries, but didn't see anything.
Only thing different about the ultimately successful deploy was it showed running all unit tests. On previous unsuccessful attempts it was not showing any test runs.
I think one thing that may be contributing is I had 5 different projects up/running at same time. And the Tooling/Metadata API setting appears to be a global.
Next time I need to do this I'll make sure only a single instance is running...
Thanks!