I have 1.2.0 RC1 installed in a bundled configuration (Apache/PHP) on Windows XP SP2.
It appears that the web server has lost track of the location for GDAL_DATA and/or PROJ_LIB again. I recall seeing this problem in earlier releases of MGOS as well.
When I run any of the CS tests, such as converting an EPSG code to WKT, I get an error message about not being able to open the .csv file from GDAL_DATA.
This appears to affect both the Web API and Map Agent.
If this isn't just a problem with the test pages, it will badly affect the operation of MGOS 1.2, and absolutely needs to be addressed before 1.2.0 Final.