I took a look today and found out how easy Groovy makes this, so when I have a chance I'll rewrite using the code below to make it pure Groovy and portable between *nix and Windows.
File rootDir = new File("d:/temp") // arg[0] == d:/temp
long checkTime = new Date().minus(7).time // arg[1] == 7
rootDir.eachFileRecurse {
if (it.isFile() && it.lastModified() >= checkTime) {
println "${it} [${new Date(it.lastModified())}]"
// call the method to load this image file...
}
}