I just upgraded to Version R3.037 and got a nasty surprise! The button is missing and in its place is a button that reads- Close Mach3! Did I miss a setting somewhere or will this be a permanent change? I know I can get it back with a little hard work and a new screen set, but it was very convenient in that position. Thanks.

Not sure as I use my own screen but you could easily replace that button and I wouldnt really call it hard work a couple of minutes max to do it. One thing though would be change the name of your screen once you have adapted it as if you dont the next time you upgrade it will get overwritten.
Hood

Funny what you get used too isn't it.
I still use Mach3 version 1.84 because i prefer the file / import HPGL/BMP/JPG and DXFs functions in preference to using LazyCam.
(most of my stuff originates in HPGL or DXF format so I am perhaps a little different to the average user of Mach).

Best regards, 

Tweakie.