When I start a miner as localhost in the latest version (4.0.6) which is running locally I get an error Interface Offline but the miner appears to work and mine to my selected pool, though it chooses the most inefficient algorithm (X15). I have managed profit mining set. Diagnostics and logs look clear.
Maybe you could share the log file with me via e-mail? Also, if you right click on the miner and select "View Details" and look at the profitability information. Does it looks correct?