Edwin, Xuser found a way to override the AMV Converter settings using a 3rd party application. It is fiddly to set up but works.
"AMV=--=AMV=--=AMV=--=AMV=--=AMV=--=AMV=--=AMV=-
finally wrote down a clip......
now it is possible to do any sizes of video with any fps.........
my clip in addition......
http://rapidshare.com/files/8139857/instructions.avi
super tool and amv converter in addition too......
http://rapidshare.com/files/8185628/amv_exp.exe
http://rapidshare.com/files/8137088/super_tool.exe"