Tony,
The "normal" ergo is adjusted at the bottom not the side (as the Glad is). I thought the BM ergo was just differently milled but worked identically.
There are 2 holes on the side - both for inputs, one usually has a blanking plug over it.
Mark
backing out = turn down. use an allen key to turn it out.
One thing is you reg might just be stuck. To dimantle the old style ergo you take the top off to get at the inards - you can see the line where it "breaks" just below the lip below the ASA threads.
Take it apart, dab of grease then reassemble.