The last WampDeveloper Pro v4 releases can be downloaded here:
http://www.devside.net/download/s23qw/WampDeveloper-4.2.0.3.zip
http://www.devside.net/download/s23qw/WampDeveloper-v4.2.0.4-delta.zip
* The “delta” release can just be extracted right over the 4.2.0.3 installation (overwrite everything + make sure WampDeveloper . exe is not running / open). It’s a package of 10 or so DLL files and the WampDeveloper exe file… That fixes a couple of minor bugs (mostly registration bugs).