Your R606 numbers look good and inline with what I get at power level 5 on my batch 2 unit.

2.  ASIC's have always gotten Hardware faults, that is pretty much a characteristic of ASIC's.  I don't even look at them anymore as long as my hashrate is decent, and yours is.

3.  You shouldn't need to worry about setting a minimum difficulty for any decent pool.  That setting is just so that an ASIC doesn't flood a pool with diff 1 shares before the pool adjusts to a reasonable value.  Most good pools start at a high value and adjust to a reasonable value that produces around 18 shares per minute. So don't worry about it and let the pool adjust it as the pool will do the adjustment regardless of what you set anyway.

5.  With Gekko gear you need to se VH's versions of CGMiner "."